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 over twenty five participants, including most of the players of the Russian and American teams who won the gold and silver medals respectively. Signed by several members of the Russian team who won their eighth consecutive gold medal, including TIGRAN PETROSIAN (1929-1984) Soviet-Armenian chess grandmaster. Knicknamed "Iron Tigran" due to his almost-impenetrable defensive playing style. World Chess Champion from 1963 to 1969, BORIS SPASSKY (1937-2025) Russian chess grandmaster, World Chess Champion from 1969 to 1972. Spassky played three world championship matches, he lost to Tigran Petrosian in 1966; then defeated Petrosian in 1969 to become world champion; and then lost to Bobby Fisher in the famous match in 1972, 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. Also signed by several members of the US team who won the silver medal, including ROBERT FISCHER (1943-2008) Known as Bobby Fischer. American-born Icelandic chess grandmaster, World Chess Champion 1972-75. A chess prodigy, widely considered one of the greatest players of all times, Robert Byrne (1928-2013) A university professor who became chess grandmaster, US champion in 1972, Nicholas Rossolimo (1910-1975) Russian-born chess grandmaster, William Addison (1933-2008), Paul Benko (1928-2019) Hungarian-born chess grandmaster. Furthermore signed by several international players who participated in the 1966 Havana Chess Olympiad, including Arturo Pomar (1931-2016) Spanish chess grandmaster, first Spanish to get the award, Miguel Najdorf (1910-1997) Argentinean chess grandmaster, and many more chess players from Canada, Yugoslavia, Checoslovakia, Finland, United Kingdom, Sweden and others. Postmarked to the front and verso with several commemorative stamps. G to VG