+<!-- Copyright (C) 2000, HELM Team -->
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+<!-- This file is part of HELM, an Hypertextual, Electronic -->
+<!-- Library of Mathematics, developed at the Computer Science -->
+<!-- Department, University of Bologna, Italy. -->
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+<!-- GNU General Public License for more details. -->
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+<!-- You should have received a copy of the GNU General Public License -->
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+<!-- Foundation, Inc., 59 Temple Place - Suite 330, Boston, -->
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+<!-- For details, see the HELM World-Wide-Web page, -->
+<!-- http://cs.unibo.it/helm/. -->
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