Raphael A. Finkel John P. Fishburn Improved Speedup Bounds for Parallel Alpha-Beta Search. 89-92 1983 5 IEEE Trans. Pattern Anal. Mach. Intell. 1 http://dx.doi.org/10.1109/TPAMI.1983.4767350 db/journals/pami/pami5.html#FinkelF83