Derek Thomson vs Coenraad Zuidema
Wch U20 fin-A The Hague NED round 8 1961.08.29
Nimzo-Indian Defense: Classical Variation 0-1

Coenraad Zuidema vs Gennady Borisovich Sosonko
NED-chT Amsterdam NED round 9 1976.05.01
Sicilian Defense: Dragon Variation, Yugoslav Attack 0-1

Coenraad Zuidema vs Maarten D Etmans
NED-ch Leeuwarden NED round 5 1969.04.04
Modern Defense 0-1