IBM international
The IBM international chess tournament was a series of very strong chess tournaments held in the Amsterdam, Netherlands from 1961 to 1981, and was sponsored by IBM. The list of winners of the main group includes five world champions.
IBM international chess tournament 1974
Amsterdam (Netherlands)
Vladimir Tukmanov
IBM international chess tournament 1973
Amsterdam (Netherlands)
Albin Planinc
IBM international chess tournament 1962
Amsterdam (Netherlands)
Moshe Czerniak
IBM international chess tournament 1962
Amsterdam (Netherlands)
Hiong Liong Tan
IBM international chess tournament 1961
Amsterdam (Netherlands)
Christian Langeweg