"Nederland, Indexen van de Archieven, Primaire Archiefstukken (BS en DTB), 1600-2000," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:QLMX-1Q22 : 22 August 2017), Nicolas Heinrich Grün in entry for Josephus Kamphues and Adelheid Anna Grün, Marriage 14 Nov 1874, Amstelveen, Noord-Holland, Netherlands; from database, openarchives (https://www.openarch.nl : 2016); citing Haarlem, inventory number , record number 75; ; Noord-Hollands Archief.

"Netherlands, Noord-Holland, Civil Registration, 1811-1950", database with images, FamilySearch (https://www.familysearch.org/ark:/61903/1:1:6DMX-4VCP : 6 December 2021), Nicolaas Heinrich Grün in entry for Adelheid Anna Grün, 1909.