Question: What is the surname of the person the Czech winner of 12 Grand Slam doubles titles and four Grand Slam mixed doubles titles defeat in the 1998 wimbledon women's singles semifinals?
Sentence (from "1998 Wimbledon Championships – Women's Singles"): Martina Hingis was the defending champion, but she was defeated by Jana Novotná in the semifinals in a rematch of last year's final.
Relevant evidence: Yes