+ <news date="2014 June 9.">
+ "Big tree" strong normalization
+ for simply typed terms.
+ </news>
+ <news date="2014 April 16.">
+ lazy equivalence on local environments
+ serves as irrelevant step in "big tree" computation on closures
+ (anniversary milestone).
+ </news>
+ <news date="2014 January 20.">
+ Parametrized slicing for local environments
+ comprises both versions of this operation
+ (one from basic_1, the other used in basic_2 till now).
+ </news>
+ <news date="2013 August 7.">