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 11-04-2023 Herman Spanjer:
"Van vreemde smetten vrij" (S.R.)
 11-04-2023 Aleksandr Vlasenko:
4. 34-29 +
 11-04-2023 Herman Spanjer:
@Aleksandr:
Good news!
S.R.: "when we can only achieve a mechanism in compositions with interchangeability, the latter is permitted."
S.R. = Spanjer Rules. laugh
 11-04-2023 Aleksandr Vlasenko:
yes