Logic programming : Proc.of the joint intern. conf. and symp. on logic programming, London, 1992 / Ed. K. Apt, 1992. - XX,848 p. p. - Текст : непосредственный.
Apt K. Verification of sequential and concurrent programs / K. Apt, F. Boer, E. Olderog, 2009 r=on-line. - Текст : электронный.