- [S70] Registers van de Burgelijke Stand. Bevolkings Registers.
- [S110] Els Kloek. 1001 vrouwen uit de Nederlandse geschiedenis (Digitaal Vrouwen Lexicon). Nijmegen: VanTilt, 2013, 2018. Online at http://resources.huygens.knaw.nl/vrouwenlexicon/
- [S160] American Family Immigration History Center. Online at http://www.ellisislandrecords.org/
- [S423] (e-mail address). De VOC Site, online: http://www.vocsite.nl/
- [S520] Rian Dirksen, Compiler (e-mail address). Soldaten Genealogie, online: http://members.home.nl/riandirksen/. No longer online. Some data now at http://www.soldaten-genealogie.tk/
- [S525] Regionaal Archief Alkmaar, Compiler. Regionaal Archief Alkmaar, online: http://www.archiefalkmaar.nl/
- [S683] Helen Rydell, correspondence. May 2012 from e-mail address to Afina Broekman.
- [S747] Yvonne de Ridder, correspondence. February 2013 from e-mail address to Afina Broekman.
- [S770] Gemeente Archief Amsterdam. Online database. Index and/or images available at https://stadsarchief.amsterdam.nl/archieven/archiefbank/indexen/index.nl.html
- [S865] Alfons Santen, Compiler (e-mail address). Website Borne, online: http://www.xanten.org/gendotnet/
- [S866] Guus Nijhuis, Compiler. Gezinsreconstructies Vollenhove, online: http://www.genealogieonline.nl/en/gezinsreconstructies-vollenhove/
- [S892] Databases Erfgoed Leiden en Omstreken. Unknown location. 1595-1950.. Index and/or images available at https://www.erfgoedleiden.nl/
- [S964] Holtman, Hans. Almelo Zeshonderd, 2019. Online at https://www.facebook.com/hans.holtmann.9828