CHESS GRANDMASTERS: Two excellent multiple signed attractive commemorative first day cover envelopes issued on the occasion of the 17th Chess Olympiad ("XVII Olimpiada Mundial de Ajedrez") held in Havana, Cuba, in November 1966, signed by close to twenty participants each, in total close to 40 autographs, being players of many different countries participating in the Chess Olympiad, including the Russian team who won the gold medal. The Russian team won their eighth consecutive gold medal. Signed to one of the commemorative first day cover envelope by BORIS SPASSKY (1937-2025) Russian Chess Grandmaster, World Chess Champion, holding the title from 1969 to 1972. Spassky played three world championship matches, he lost to Tigran Petrosian in 1966, later defeated Petrosian in 1969 to become world champion, and finally lost to Bobby Fischer in a famous match in 1972; the second envelope is signed by few more Russian chess players; Leonid Stein (1934-1973) Soviet chess Grandmaster. He won three USSR Chess Championships in 1963. 1965 & 1966 and was among the world's top ten players during that era. Stein died of a heart attack at the very early age of 38 as he prepared to leave for the European chess championships in Bath, England. At the time of death, he was still considered as one of the main contenders for World Championship; Lev Polugaevsky (1934-1995) Soviet chess grandmaster, a frequent contender for the World Championship. He was one of the strongest players in the world from the early 1960s until the late 1980s; Vasily Smyslov (1921-2010) World Chess Champion 1957-58, Soviet-Russian chess grandmaster. He was a a candidate for the World Chess Champioship on eight occasions between 1948 and 1985. His total of 17 Chess Olympiad medals won is an all-time record. In five European Team Championships, Smyslov won ten gold medals. Also signed by multiple players from different countries such as Spain, Morocco (Moktar Kadri & Ahmed Bennis), Belgium (Mollekens), South-Africa (Leon Wilken), Austria, Czechoslovakia, Greece, Tunisia, Sweden, Norway (Ragnar Hoen), Portugal, Mexico, etc... All have signed in bold inks. Postmarked to the front and verso with several commemorative stamps. G to VG