Netherlands, Archival Indexes, Vital Records," database, FamilySearch (
https://familysearch.org/ark:/61903/1:1:QLN9-QVFZ : 30 August 2017), Johannes Baarda in entry for Derk Baarda, Death 15 Dec 1940, Ulrum, Groningen, Nederland; from database, openarchives (https://www.openarch.nl : 2016); citing Ulrum, archive , inventory number , record number 41; ; AlleGroningers.