castling 3 times in one game?

Jan 7, 2009, 10:27 AM |

as shown at Chess Records

during the Heidenfeld - Kerins, Dublin 1973... I see that the Blk queen is attacking a square that white caslted across, something I thought was a no-no, so I am confused...which is the 3rd castle in the game.

Is this legal???

Inquiring Minds need to Know????