Mikhail Moiseyevich Botvinnik was a Soviet and Russian chess grandmaster who held five world titles in three different reigns. The sixth World Chess Champion, he also worked as an electrical engineer
Reuben C. Fine was an American chess player, psychologist, university professor, and author of many books on both chess and psychology. He was one of the strongest chess players in the world from the
Fine in 1961
Fine playing against Paul Keres at AVRO tournament in 1938