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-<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
-<html>
-<head>
-  <meta content="text/html; charset=UTF-8" http-equiv="content-type">
-  <title>lambdadelta home page</title>
-  <meta content="Ferruccio Guidi" name="author">
-  <meta content="The formal system lambdadelta" name="description">
-  <link rel="shortcut icon" href="download/crux_16.ico">
-</head>
-<body>
-<div style="text-align: center;"> <br>
-<a href="http://lambdadelta.info"><img alt="[Crux Logo]"
- title="The Crux" src="download/crux_32.png"
- style="border: 0px solid ; width: 32px; height: 32px;"></a>
-<h1>The Formal System λδ (lambdadelta)<br>
-</h1>
-<h2>Towards the unification of terms, types, environments and contexts</h2>
-<img style="width: 95%; height: 4px;" alt="[Separator]"
- title="Separator" src="download/rainbow.png"><br>
-<table
- style="text-align: left; width: 95%; margin-left: auto; margin-right: auto;"
- border="0" cellpadding="2" cellspacing="20">
-  <tbody>
-    <tr>
-      <td style="vertical-align: top;">
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml" dir="ltr" lang="en-us">
+  <head>
+    <meta http-equiv="Content-Language" content="en-us" />
+    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
+    <meta http-equiv="Content-Style-Type" content="text/css" />
+    <meta name="author" content="Ferruccio Guidi" />
+    <meta name="description" content="\lambda\delta home page" />
+    <title>\lambda\delta home page</title>
+    <link rel="stylesheet" type="text/css" href="http://lambdadelta.info/css/ld_web.css" />
+    <link rel="stylesheet" type="text/css" href="http://lambdadelta.info/css/lddl.css" />
+    <link rel="stylesheet" type="text/css" href="http://lambdadelta.info/css/xhtbl.css" />
+    <link rel="shortcut icon" href="http://lambdadelta.info/images/crux_16.ico" />
+  </head>
+  <body lang="en-US">
+    <div class="spacer">
+      <a href="http://lambdadelta.info/">
+        <img class="icon32" alt="[lambdadelta home]" title="lambdadelta home" src="http://lambdadelta.info/images/crux_32.png" />
+      </a>
+    </div>
+    <div class="head1">The Formal Systems of the λδ (\lambda\delta) Family</div>
+    <div class="spacer">
+      <img class="rule" alt="[Spacer]" title="lambdadelta rainbow rule" src="http://lambdadelta.info/images/rainbow.png" />
+    </div>
+    <div xmlns:ld="http://lambdadelta.info/" class="spacer">
+      <br />
+    </div>
+    <div xmlns:ld="http://lambdadelta.info/" class="text">
+      <table cellpadding="4" cellspacing="0">
+        <tbody>
+          <tr>
+            <td class="snns capitalize italic sky">
+              <a href="http://lambdadelta.info/index.html">home</a>
+            </td>
+            <td class="snns capitalize italic magenta">
+              <a href="http://lambdadelta.info/news.html">news</a>
+            </td>
+            <td class="snns capitalize italic white">
+              <a href="http://lambdadelta.info/specification.html">specification</a>
+            </td>
+            <td class="snnn capitalize italic white">
+              <br />
+            </td>
+            <td class="snnn capitalize italic white">
+              <br />
+            </td>
+            <td class="snns capitalize italic orange">
+              <a href="http://lambdadelta.info/documentation.html">documentation</a>
+            </td>
+            <td class="snns capitalize italic green">
+              <a href="http://lambdadelta.info/implementation.html">implementation</a>
+            </td>
+            <td class="ssnn capitalize italic green">
+              <br />
+            </td>
+          </tr>
+          <tr>
+            <td class="snns capitalize sky">
+              <a href="http://lambdadelta.info/index.html#foreword">foreword</a>
+            </td>
+            <td class="snns capitalize magenta">
+              <a href="http://lambdadelta.info/news.html#milestones">milestones</a>
+            </td>
+            <td class="snns capitalize white">
+              <a href="http://lambdadelta.info/specification.html#v2">version 2</a>
+            </td>
+            <td class="snnn capitalize white">(<a href="http://lambdadelta.info/ground_2.html">background</a> - <a href="http://lambdadelta.info/basic_2.html">core</a> - <a href="http://lambdadelta.info/apps_2.html">applications</a>)</td>
+            <td class="snnn capitalize white">
+              <br />
+            </td>
+            <td class="snns capitalize orange">
+              <a href="http://lambdadelta.info/documentation.html#v2">version 2</a>
+            </td>
+            <td class="snns capitalize green">
+              <a href="http://lambdadelta.info/implementation.html#lddl">library</a>
+            </td>
+            <td class="ssnn capitalize green">(<a href="http://lambdadelta.info/static/lddl/">static LDDL directory</a>)</td>
+          </tr>
+          <tr>
+            <td class="snss capitalize sky">
+              <a href="http://lambdadelta.info/index.html#citations">citations</a>
+            </td>
+            <td class="snss capitalize magenta">
+              <a href="http://lambdadelta.info/news.html#visibility">visibility</a>
+            </td>
+            <td class="snss capitalize white">
+              <a href="http://lambdadelta.info/specification.html#v1">version 1</a>
+            </td>
+            <td class="snsn capitalize white">(<a href="http://lambdadelta.info/ground_1.html">background</a> - <a href="http://lambdadelta.info/basic_1.html">core</a>)</td>
+            <td class="snsn capitalize white">(<a href="http://lambdadelta.info/static/matita/lambdadelta/">static HELM directory</a>)</td>
+            <td class="snss capitalize orange">
+              <a href="http://lambdadelta.info/documentation.html#v1">version 1</a>
+            </td>
+            <td class="snss capitalize green">
+              <a href="http://lambdadelta.info/implementation.html#helena">helena</a>
+            </td>
+            <td class="sssn capitalize green">
+              <br />
+            </td>
+          </tr>
+        </tbody>
+      </table>
+    </div>
+    <!-- ===================================================================== -->
+    <div xmlns:ld="http://lambdadelta.info/" class="head2dx" id="milestones">Milestones <img class="icon37" alt="[spacer]" title="lambdadelta butterfly" src="http://lambdadelta.info/images/b3.png" />
+    </div>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">December 2015.</span>
+        <a href="http://lambdadelta.info/documentation.html#ldJ3a">Second journal paper on λδ</a>
+      accepted for publication.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph gamma">December 2015.</span>
+        <a href="http://lambdadelta.info/implementation.html#v3">"Helena 0.8.3"</a> is released.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph delta">August 2015.</span>
+      The specification of λδ version 2A1 is concluded.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph gamma">June 2015.</span>
+      The corrected specification of Landau's "Grundlagen der Analysis"
+      is validated in a λProlog implementation of λδ version 3.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph delta">March 2015.</span>
+      The specification of λδ version 1 is validated by
+      <a href="http://matita.cs.unibo.it/">Matita 0.99.2</a>.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph gamma">February 2015.</span>
+        <a href="http://lambdadelta.info/implementation.html#v2">"Helena 0.8.2"</a> is updated.
       <ul>
-        <li><a href="index.html">Foreword</a></li>
-      </ul>
+          <li>
+         The translated specification of Landau's "Grundlagen der Analysis"
+         is validated in CC by <a href="http://coq.inria.fr/">Coq 8.4.3</a>. 
+      </li>
+        </ul>
+      </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph delta">January 2015.</span>
+      The specification of <a href="http://lambdadelta.info/specification.html#v1">λδ version 1</a>
+      is updated with backports from the abandoned specification of λδ version 2.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph gamma">December 2014.</span>
+        <a href="http://lambdadelta.info/implementation.html#v2">"Helena 0.8.2"</a> is released.
       <ul>
-        <li>News</li>
-      </ul>
+          <li>
+         The corrected specification of Landau's "Grundlagen der Analysis"
+         is validated in λδ version 3. 
+      </li>
+        </ul>
+      </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph gamma">October 2014.</span>
+        <a href="http://lambdadelta.info/documentation.html#ldJ2a">λδ version 2A1</a>
+      is released.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph beta">July 2014.</span>
+      A new version of this site is online.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph beta">June 2014.</span>
+        <a href="http://lambdadelta.info/documentation.html#ldP2c">First communication on λδ version 2.</a>
+      </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">December 2012.</span>
+      The character "_" is removed from the denomination "lambda_delta":
       <ul>
-        <li><a href="documentation.html">Papers</a></li>
-      </ul>
+          <li>
+         The denomination "\lambda\delta" is used in λδ-related texts.
+      </li>
+          <li>
+         The denomination "lambdadelta" is used in λδ-related identifiers.
+      </li>
+          <li>
+         Permanent λδ URL acquired:
+         <a href="http://lambdadelta.info/">http://lambdadelta.info/</a>
+         (pointing at this site).
+      </li>
+        </ul>
+      </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">September 2011.</span>
+      The denomination "lambda-delta" changes to "lambda_delta":
       <ul>
-        <li><a href="implementation.html">Resources</a><br>
-        </li>
-      </ul>
-      </td>
-      <td style="vertical-align: top; text-align: left;">
-      <h3 style="text-align: right;">News <img
- style="width: 37px; height: 37px;" alt="[Butterfly]" title="Butterfly"
- src="download/b5.png"></h3>
-      <ul>
-        <li><span style="font-weight: bold;">September 2011.</span> The
-denomination "lambdadelta" changes to "lambdadelta".
-          <ul>
-            <li>The character "-" is reserved in λδ textual syntax
-(recognized by <span style="font-style: italic;">Helena 0.8.1</span>).
-            </li>
-            <li>Eventually, the occurrences of the character "-" will
-be replaced by "_" in all λδ-related identifiers.</li>
-            <li>In particular, this refactoring involves file names and
-path names.</li>
-            <li>The permanent λδ URL is sheduled to become <span
- style="font-style: italic;">http://lambdadelta.info</span> on
-December 2012.<br>
-            </li>
-          </ul>
-        </li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">April 2011.</span> The
-specification of λδ version 2 and related topics is restarted in <a
- href="http://matita.cs.unibo.it/">Matita 0.5</a>.
-          <ul>
-            <li><a href="apps_2.html">Here</a> is a page about the
-topics related to the specification (Applications).</li>
-            <li><a href="basic_2.html">Here</a> is a page about the
-specification (Core). </li>
-          </ul>
-        </li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">December 2010.</span>
-Permanent λδ URL acquired: <a href="http://lambdadelta.info">http://lambdadelta.info</a>
-(pointing at this site). <br>
-          <span style="font-weight: bold;"></span></li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">November 2010.</span> <span
- style="font-style: italic;">Helena 0.8.1</span> is released. <br>
-        </li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">September 2009.</span> <span
- style="font-style: italic;">Helena 0.8.0</span> is released and the <a
- href="implementation.html#lddl">λδ Digital Library</a> is started.<br>
-          <span style="font-weight: bold;"></span></li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">June 2009.</span> <span
- style="font-style: italic;">Helena</span>, a <a
- href="implementation.html#helena">validator for λδ version 2</a>, is
-available as a part of the <a href="http://helm.cs.unibo.it/">HELM</a>
-software. <br>
-        </li>
-      </ul>
-      <span style="font-weight: bold;"></span>
-      <ul>
-        <li><span style="font-weight: bold;">September 2008.</span>
-This site is online.<br>
-        </li>
-      </ul>
-      <span style="font-weight: bold;"></span>
-      <ul>
-        <li><span style="font-weight: bold;">July 2008.</span> <a
- href="documentation.html#ldp5">First journal paper on λδ</a> accepted
-for publication.</li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">July 2008.</span> First <a
- href="http://helm.cs.unibo.it/procedural/">procedural reconstruction</a>
-for <a href="http://matita.cs.unibo.it/">Matita 0.5</a> of the <a
- href="implementation.html#ldp1">λδ proof scripts for Coq 7.3.1</a>.<br>
-        </li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">June 2008.</span> The <a
- href="implementation.html#static">HTML pages of the specification of
-λδ version 1 for Matita 0.5</a> are online.<br>
-          <span style="font-weight: bold;"></span></li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">May 2008.</span> The
-specification of λδ version 1 is closed.<br>
-          <span style="font-weight: bold;"></span></li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">March 2008.</span> The
-specification of λδ version 2 is started with Coq 7.3.1 (false start). </li>
-      </ul>
-<!--          <ul>
-            <li>native type assignment with new rules for application: <span
- style="font-style: italic;">nty</span> (it replaces <span
- style="font-style: italic;">ty3</span>);<br>
-            </li>
-            <li>parallel conversion on focalized terms: <span
- style="font-style: italic;">fpcs</span> (it replaces <span
- style="font-style: italic;"></span><span style="font-style: italic;">pc3</span>);
-              <br>
-            </li>
-            <li>new weak parallel reduction on environments: <span
- style="font-style: italic;">wcpr</span> <span
- style="font-style: italic;"></span>(it is based on <span
- style="font-style: italic;">fpr</span> and replaces <span
- style="font-style: italic;">wcpr0</span>);&nbsp; <br>
-            </li>
-            <li>parallel reduction on focalized terms: <span
- style="font-style: italic;">fpr</span> and <span
- style="font-style: italic;">fprs</span> (they replace <span
- style="font-style: italic;"></span><span style="font-style: italic;"></span><span
- style="font-style: italic;">pr2</span>, <span
- style="font-style: italic;">pr3</span>); <br>
-            </li>
-          </ul>
-          <ul>
-            <li>new thinning relation: <span
- style="font-style: italic;">drop</span>
-(it replaces the old <span style="font-style: italic;">drop</span>, <span
- style="font-style: italic;">clear</span>, <span
- style="font-style: italic;">getl</span>, <span
- style="font-style: italic;">cimp</span>, <span
- style="font-style: italic;">drop1</span>);</li>
-            <li>new shift function: <span style="font-style: italic;">shift</span>:
-(it
-replaces
-
-              <span style="font-style: italic;">app1</span>);</li>
-            <li>new length function for environments: <span
- style="font-style: italic;">clen</span>;<br>
-            </li>
-            <li>new relocation function: <span
- style="font-style: italic;">lift</span> (it replaces old <span
- style="font-style: italic;">lift</span>, <span
- style="font-style: italic;">lift1</span>);<br>
-            </li>
-            <li>new term structure with polarity indicators and no
-distinction between binding and flat items;</li>
-            <li>new general theory of relocation (comprises new
-relocation functions: <span style="font-style: italic;">s</span>, <span
- style="font-style: italic;">r</span>);</li>
-            <li>we removed context-free reduction and conversion (<span
- style="font-style: italic;">pr0</span>, <span
- style="font-style: italic;">pr1</span>, <span
- style="font-style: italic;">pc1</span>);<br>
-            </li>
-            <li>we removed greedy substitution (<span
- style="font-style: italic;"></span><span style="font-style: italic;">csubst0</span>,
-              <span style="font-style: italic;">csubst1</span>, <span
- style="font-style: italic;">fsubst0</span>, <span
- style="font-style: italic;">subst0</span>, <span
- style="font-style: italic;">subst1</span>);<br>
-            </li>
-            <li>we removed level indicators on environments (<span
- style="font-style: italic;">cbk</span>).</li>
-          </ul>
--->
-      <ul>
-        <li><span style="font-weight: bold;">September 2007.</span> The
-          <a href="implementation.html#dynamic">specification of λδ
-version 1 for Matita 0.4</a> is online.</li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">November 2006.</span> <a
- href="documentation.html#ldp3">λδ version 1</a> is released.</li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">December 2005.</span> <a
- href="documentation.html#ldt1">First communication on λδ</a>.<br>
-        </li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">May 2004.</span> The <a
- href="implementation.html#ldp1">specification of λδ version 1</a> is
-started with Coq 7.3.1.<br>
-        </li>
-      </ul>
-      <h3 style="text-align: right;">Visibility <img
- style="width: 37px; height: 37px;" alt="[Butterfly]" title="Butterfly"
- src="download/b4.png"></h3>
-      <ul>
-        <li><span style="font-weight: bold;">February 2012.</span> The <a
- href="http://www.google.com/">Google</a> search for <span
- style="color: rgb(255, 0, 0);">formal system lambda delta</span> gives
-5 resources about λδ in the first 6 results.<br>
-        </li>
-      </ul>
-      <ul>
-        <li><span style="font-weight: bold;">February 2012.</span> The <a
- href="http://www.yahoo.com/">Yahoo</a> search <span
- style="color: rgb(255, 0, 0);">formal system lambda delta</span> gives
-this site as the first result.</li>
-      </ul>
-      </td>
-    </tr>
-  </tbody>
-</table>
-<br>
-<a href="http://validator.w3.org/check?uri=referer"><img
- alt="[Valid HTML 4.01 Transitional]"
- title="Valid HTML 4.01
-          Transitional"
- src="http://www.w3.org/Icons/valid-html401"
- style="border: 0px solid ; width: 88px; height: 31px;"></a> <a
- href="http://www.anybrowser.org/campaign/"><img
- alt="[Use Any
-          Browser Here]" title="Use Any Browser Here"
- src="download/globe_trans.png"
- style="border: 0px solid ; width: 147px; height: 42px;"></a> <img
- style="width: 88px; height: 31px;" alt="[PNG Used Here]"
- title="PNG Used Here" src="download/PNGnow2.png"><br>
-<br>
-Last update 2012-12-01 by <a href="http://www.cs.unibo.it/%7Efguidi/">Ferruccio
-
-Guidi</a><br>
-</div>
-</body>
+          <li>
+         The character "-" is reserved in λδ textual syntax
+         (recognized by "Helena 0.8.1").            
+      </li>
+          <li>
+         Eventually, the occurrences of the character "-"
+         will be replaced by "_" in all λδ-related identifiers.
+      </li>
+          <li>
+         In particular, this refactoring involves file names and path names.
+      </li>
+        </ul>
+      </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">April 2011.</span>
+      The specification of <a href="http://lambdadelta.info/specification.html#v2">λδ version 2</a>
+      and related topics is restarted in
+      <a href="http://matita.cs.unibo.it/">Matita 0.5</a>.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph delta">February 2011.</span>
+      The specification of λδ version 2 with Coq 7.3.1 is abandoned.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">December 2010.</span>
+      Transient λδ URL acquired: http://lambda-delta.info/ (expires on December 2012). 
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph beta">November 2010.</span>
+        <a href="http://lambdadelta.info/implementation.html#v1">"Helena 0.8.1"</a> is released.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph beta">September 2009.</span>
+        <a href="http://lambdadelta.info/implementation.html#v0">"Helena 0.8.0"</a> is released and the
+      <a href="http://lambdadelta.info/implementation.html#lddl">λδ Digital Library</a> is started.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">June 2009.</span>
+      "Helena", a <a href="http://lambdadelta.info/implementation.html#helena">validator for λδ version 2</a>,
+      is available as a part of the <a href="http://helm.cs.unibo.it/">HELM</a> software. 
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">September 2008.</span>
+      This site is online.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph delta">July 2008.</span>
+        <a href="http://lambdadelta.info/documentation.html#ldJ1a">First journal paper on λδ</a>
+      accepted for publication.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph delta">July 2008.</span>
+      First <a href="http://helm.cs.unibo.it/procedural/">procedural reconstruction</a>
+      for <a href="http://matita.cs.unibo.it/">Matita 0.5</a>
+      of the λδ version 1 for Coq 7.3.1.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph delta">June 2008.</span>
+      The <a href="http://lambdadelta.info/specification.html#static1">
+         HTML pages of the specification of λδ version 1 for Matita 0.5</a>
+      are online.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph delta">May 2008.</span>
+      The specification of λδ version 1 is concluded.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">March 2008.</span>
+      The specification of λδ version 2 is started with Coq 7.3.1 (false start).
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph gamma">September 2007.</span>
+      The <a href="http://lambdadelta.info/specification.html#dynamic1">
+         specification of λδ version 1 for Matita 0.4</a>
+      is online.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph gamma">November 2006.</span>
+        <a href="http://lambdadelta.info/documentation.html#ldR1b">λδ version 1</a>
+      is released.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph beta">December 2005.</span>
+        <a href="http://lambdadelta.info/documentation.html#ldP1a">First communication on λδ version 1</a>.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">May 2004.</span>
+      The specification of <a href="http://lambdadelta.info/specification.html#v1">λδ version 1</a>
+      is started with Coq 7.3.1.
+   </li>
+    </ul>
+    <!-- ===================================================================== -->
+    <div xmlns:ld="http://lambdadelta.info/" class="head2dx" id="visibility">Visibility <img class="icon37" alt="[spacer]" title="lambdadelta butterfly" src="http://lambdadelta.info/images/b3.png" />
+    </div>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">June 2014.</span>
+      The <a href="http://www.google.com/">Google</a>
+      search for "formal system lambda delta" gives
+      5 resources about the λδ family in the first 6 results.
+   </li>
+    </ul>
+    <ul xmlns:ld="http://lambdadelta.info/">
+      <li>
+        <span class="emph alpha">June 2014.</span>
+      The <a href="http://www.yahoo.com/">Yahoo</a>
+      search for "formal system lambda delta" gives
+      4 resources about the λδ family in the first 5 results.
+   </li>
+    </ul>
+    <div class="spacer">
+      <img class="rule" alt="[Spacer]" title="lambdadelta rainbow rule" src="http://lambdadelta.info/images/rainbow.png" />
+    </div>
+    <div xmlns:ld="http://lambdadelta.info/" class="spacer">
+      <br />
+    </div>
+    <div xmlns:ld="http://lambdadelta.info/" class="spacer">
+      <a href="http://validator.w3.org/check?uri=referer">
+        <img class="w3c" alt="[Valid XHTML 1.1]" title="Valid XHTML 1.1" src="http://www.w3.org/Icons/valid-xhtml11-blue" />
+      </a>
+      <a href="http://jigsaw.w3.org/css-validator/check/referer">
+        <img class="w3c" alt="[Valid CSS level 2]" title="Valid CSS level 2" src="http://www.w3.org/Icons/valid-css2-blue" />
+      </a>
+      <a href="http://www.w3.org/XML/">
+        <img class="w3c" alt="[Generated from XML via XSL]" title="Generated from XML via XSL" src="http://lambdadelta.info/images/xml_xsl2.png" />
+      </a>
+      <a href="http://www.w3.org/Graphics/PNG/">
+        <img class="w3c" alt="[PNG used here]" title="PNG used here" src="http://lambdadelta.info/images/PNGnow2.png" />
+      </a>
+      <a href="http://www.anybrowser.org/campaign/">
+        <img class="w3c" alt="[Viewable with any browser]" title="Viewable with any browser" src="http://www.anybrowser.org/campaign/bvgraphics/abtfile.png" />
+      </a>
+    </div>
+    <div xmlns:ld="http://lambdadelta.info/" class="spacer">
+      <br />
+    </div>
+    <div xmlns:ld="http://lambdadelta.info/" class="spacer">Last update: Sat, 23 Jan 2016 00:45:18 +0100</div>
+  </body>
 </html>