ngsq numbering system - SERP Analysis

https://en.wikipedia.org/wiki/Genealogical_numbering_systems

https://www.ngsgenealogy.org/numbering-genealogy/

http://higdonfamily.org/research-tips-for-advanced/numbering-systems-for-genea/descending-numbering-system/ngsq-system-1903.html

https://treeandleaf.org/numbering/

https://familytreewebinars.com/wp-content/uploads/2021/07/webinar-free1533139842.pdf

https://www.familysearch.org/en/wiki/Genealogy_Numbering_Systems_-_International_Institute

https://cyndislist.com/numbering/ngsq/

https://people.math.carleton.ca/~rhfischl/GENEALOGY/TRIPLE_LOVE_DVD/GENEALOGICAL_CHARTS%2BGENEALOGY/0d_genealogical_numbering_systems.pdf

https://www.thoughtco.com/numbering-your-family-tree-1420742

http://www.vanvoorhees.org/docs/number_system.php