A really long term queen sacrifice

While building up my collection of queen sacrifices (for coaching purposes), I came across this monster of a game. Nick de Firmian gives up his queen on move 13 before eventually winning on move 110. To be fair, he did get three pieces in return for it, but to play almost 100 moves while making sure you don't fall for a queen fork does take some doing.
I'm not sure what Jon Speelman (as black) thought of it all, but hopefully I will remember to ask him next time I see him.


De Firmian,Nick E (2395) - Speelman,Jonathan S (2410) [B57]
WchT U26 fin-A Mexico City (6), 19.08.1977