Optimization techniques: Proceedings of the 9th IFIP conference on optimization techniques, Warsaw, September 4–8, 1979, Part 1 and Part 2: K. IRACKI, K. MALANOWSKI and S. WALUKIEWICZ (Eds.) Volume 22 and 23 in: Lecture Notes in Control and Information Sciences, Springer, Berlin, 1980, xvi/xv + 569/621 pages, both DM 59.-, soft cover