- FamilySear
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 13 Jun 2016), entry for Eustace I of Boulogne, person ID 99QR-V1S.
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 13 Jun 2016), entry for Eustace I Boulogne, person ID 9CSL-MCV.
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 13 Jun 2016), entry for Eustace I ( Count Of Boulogne), person ID L7DH-YS7.
» Quellen » Familienstammbaum M. Tolsma » Genealogie Online">
- FamilySear
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 13 Jun 2016), entry for Eustace I of Boulogne, person ID 99QR-V1S.
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 13 Jun 2016), entry for Eustace I Boulogne, person ID 9CSL-MCV.
- FamilySearch Family Tree (http://www.familysearch.org) - "FamilySearch," database, \i FamilySearch\i0 - The Church of Jesus Christ of Latter-day Saints - accessed 13 Jun 2016), entry for Eustace I ( Count Of Boulogne), person ID L7DH-YS7.
» Quellen » Familienstammbaum M. Tolsma » Genealogie Online">