Oscar Humberto Castro Rojas vs Borislav Ivkov - Sao Paulo 1978.05.??

Oscar Humberto Castro Rojas vs Borislav Ivkov<br>Sao Paulo Sao Paulo BRA round 5 1978.05.??<br>Vienna Game: Heyde Variation 1-0<br>https://www.chessgames.com/perl/chessgame?gid=1062232 --- Send in a voice message: https://anchor.fm/blindfoldchess/message