William E. (Bill) Toikka,
an American electrical engineer, computer scientist, chess player and former chess programmer, associated with Applied Data Research in Princeton, NJ. As member of the engineering honor society Tau Beta Pi, he graduated from Lehigh University in 1962  .
Along with Fred Swartz, Victor Berman, Joe Winograd, Mike Alexander and Ira Ruben, William Toikka was co-author of the chess program CHAOS  , whose development started at RCA Systems Programming division in Cinnaminson, NJ. CHAOS was one of the strongest programs of the 70s and early 80s, using an unique, knowledge based and selective best-first, iterative widening approach  , keeping the search tree in memory.
- Pennsylvania Alpha Graduates 1961-1970 from Lehigh University, Tau Beta Pi
- Pi Kappa Alpha - Article
- pp. 52, Table I. History of the ACM Tournaments from Ben Mittman, Monroe Newborn (1980). Computer chess at ACM 79: the tournament and the man vs. man and machine match. Communications of the ACM, Vol. 23, Issue 1, pdf from The Computer History Museum
- The Eleventh ACM's North American Computer Chess Championship as pdf reprint from The Computer History Museum
- Photo courtesy Joe Winograd
- Chaos vs. Duchess at the 10th ACM North American Computer Chess Championship, 1979 Gift of Monroe Newborn from The Computer History Museum