[Event "Dutch Championship KNDB 1957"]
[Site ""]
[White "Boer, Siem"]
[Black "Roozenburg, Willem"]
[Annotator "Gerrit Boom"]
[Result "1-1"]
[GameType "20"]
[Round "12"]
[Date "1957.02.24"]
[WhiteTime ""]
[BlackTime ""]
[TimeControl ""]
[WhiteUrl "http://toernooibase.kndb.nl/Afbeeldingen/Spelers/2942.jpg"]
[BlackUrl "http://toernooibase.kndb.nl/Afbeeldingen/Spelers/5351.jpg"]
[WhiteTitle ""]
[BlackTitle ""]
[WhiteRating ""]
[BlackRating ""]
[DamboTopLine "Dutch Championship KNDB 1957 Round 12"]
[DamboBottomLine "Boer, Siem - Roozenburg, Willem 1-1"]
[FEN "B:W16,26,29,31,33,35,36,37,38,39,41,42,43,45,46:B2,3,4,6,7,9,11,12,15,17,18,20,22,24,25"] 23. ... 25-30 met de niet te pareren dreiging 22-28.