- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 24 Jun 2016), entry for Guillaume I Le Conqu?c rant de Normandie, person ID 9CZG-1BJ.
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 24 Jun 2016), entry for Guillaume I de Normandie, person ID 9H8Q-ZC7.
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 24 Jun 2016), entry for Guillaume I " Le Conquberant" De Normandie, person ID 9Z4P-V15.
» Les sources » Arbre généalogique M. Tolsma » Généalogie Online">
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 24 Jun 2016), entry for Guillaume I Le Conqu?c rant de Normandie, person ID 9CZG-1BJ.
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 24 Jun 2016), entry for Guillaume I de Normandie, person ID 9H8Q-ZC7.
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 24 Jun 2016), entry for Guillaume I " Le Conquberant" De Normandie, person ID 9Z4P-V15.
» Les sources » Arbre généalogique M. Tolsma » Généalogie Online">