CHESS GRANDMASTERS: An excellent multiple signed attractive commemorative first day cover envelope issued on the occasion of the 17th Chess Olympiad ("XVII Olimpiada Mundial de Ajedrez") held in Havana, Cuba, in November 1966, signed by five participants, being players of the Russian team who won the gold medal. The Russian team won their eighth consecutive gold medal. Signed to the commemorative first day cover envelope by VIKTOR KORCHNOI (1931-2016) Former Soviet chess grandmaster, Swiss from 1980. He is widely considered one of the strongest players never to have become World Chess Champion. Korchnoi was a candidate for the World Championship on ten occasions between 1962 and 1991; Mikhail Tal (1936-1992) Soviet-Latvian chess grandmaster. Known as the "Magician of Riga". World champion in 1960-61. Widely regarded as a creative genius and one of the most influential players in chess history, known for his improvisation and unpredictability. He also held the record for the longest unbeaten streak in competitive chess history with 95 games; Signed twice by 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, send signature obtained the year after in 1967, 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. Signature obtained the year after in 1967 & 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. All have signed in bold blkue inks, except Spassky which did so in purple. ink Postmarked to the front and verso with several commemorative stamps. G to VG