%0 Journal Article 
%F hopcroft1969equivalence
%A Hopcroft, J.E.
%T On the equivalence and containment problems for context-free languages
%J Theory of Computing Systems
%V 3
%N 2
%P 119-124
%I Springer
%U http://www.diku.dk/hjemmesider/ansatte/henglein/papers/hopcroft1969.pdf
%D 1969
%K algexp