"Netherlands, Archival Indexes, Vital Records," database, FamilySearch (
https://familysearch.org/ark:/61903/1:1:QL4D-D92M : 22 August 2017), Johannes Baarda in entry for Magrietha Baarda, Birth 31 May 1868, Ulrum, Groningen, Nederland; from database, openarchives (https://www.openarch.nl : 2016); citing Ulrum, archive , inventory number , record number 36; ; AlleGroninger