a Dutch chess player, Woman International Master and chess GUI and chess database developer. Jessica played three Aegon Tournaments, 1993, 1994 and 1995, and was involved in the Windows GUIs and additional chess database development for Chessica  and Chessmaster 6000 and 7000  .
- Jessica Harmsen from MobyGames
- Harmsen, Jessica FIDE Chess Profile - Players Arbiters Trainers
- The chess games of Jessica Harmsen from chessgames.com
- Jessica Harmsen chess games - 365Chess.com