+-->
+ <news class="alpha" date="2018 November 1.">
+ Extended (λδ-2) and restricted (λδ-1) type rules justified.
+ </news>
+ <news class="alpha" date="2018 September 21.">
+ λδ-2A completed with
+ confluence of rt-computation and
+ preservation of validity for rt-computation.
+ </news>