| Klaas Knol + Boulina Fenna Wierema
 
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	| | Freerk Wierema  (I05993) 
Birth  25 September 1874   -- Maarhuizen, Winsum, Groningen, NetherlandsDeath  16 July 1931 (Age 56)   -- Groningen, Groningen, Groningen, Netherlands
 
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	| | Tjaakje Lettinga  (I05994) 
Birth  23 March 1869   -- Groningen, Groningen, Groningen, NetherlandsDeath  26 August 1934 (Age 65)   -- Groningen, Groningen, Groningen, Netherlands
 
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