An introduction to Kolmogorov complexity and its applications / SpringerLink (Online service), 2008 r=on-line. - Текст : электронный.
Gries D. A logical approach to discrete math / D.Gries,F.B.Schneider, 1993. - XVI,497 p. p. - Текст : непосредственный.
Gries D. Multimedia introduction to programming using java / D. Gries, P. Gries, 2005 r=on-line. - Текст : электронный.