I read your question today on the internet. A question dated from 2000*. I wonder if through all these years you got an answer? The brother off my grandmother (Anje Elizabeth Buitenwerf) emigrated to Canada. His name is Willem Buitenwerf born 5th october 1906 in Uithuizermeeden (near Bierum in the northern part of the Netherlands). I'm curious if you found these branch of the Buitenwerf family. Both my grandmother and Willem are children from Tjark Buitenwerf and Klaaske Kooi.