Jerónimo de Sosa

Jerónimo de Sosa also known as Hieronymus, Jerome or Geronimo de Sosa, was a 17th-century Spanish Franciscan friar and a genealogist who developed a genealogical numbering system of ancestors.
Sosa was a lector of theology at the royal monastery of Santa Maria [La Nova, Naples|Santa Maria la Nova] in Naples. In his work Noticia de la gran casa de los marqueses de Villafranca in 1676, he used and popularized a method based on the numbering system first published by Michaël Eytzinger in 1590.
Sosa's method was popularized on a large scale by Stephan [Kekulé von Stradonitz] in his Ahnentafel-atlas in 1898 and became known as Ahnentafel or the Sosa–Stradonitz Method.