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The Sofia Grand Prix was a men's indoor carpet court tennis tournament played in Sofia, Bulgaria as part of the ITF Grand Prix Circuit. It was first founded in 1978 as the Sofia International Indoor that event ran for one edition only. In 1980 it was revived as the Sofia Grand Prix which was staged until 1981. The successor indoor Bulgarian tournament to this is the current ATP Sofia Open
Barrett, John and Tingay, Lance. (1981) Slazengers World of Tennis. The official year book of the International Tennis Federation. Queen Press and Macdonald Futura. London. Page. 125. ISBN0362020345.
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