Chess puzzle: Can you figure out the mating sequence?

Hello Everyone,

Here is a nice puzzle that looks like a classic Queen sac for mate. White is to play. Can you work out the entire mating sequence of moves?

The game was played between Toran and O'Kelly in 1967 in Palma. It's not all that difficult because there are all these forcing moves.

From Alexandra Kosteniuk's

www.chessblog.com

Also see her personal blog at

www.chessqueen.com