María Andresa Casamayor as an 18th century Spanish Mathematician. Her only work published, Tyrocinio Arithmético, was intended to be a reference guide for the merchants that lived in Zaragoza and traded with other territories. Listen in as Ellen tells Susi more about María Andresa and how incredible she was.

References
Jochim, Mark Joseph.  "News issues 2020: Spain (Women in Science)." Philatelic Pursuits, June 20, 2020.
Practica Español. "The story of the woman who dreamed of numbers and hid under a male pseudonym."
School of Mathematics and Statistics, University of St Andrews, Scotland. "María Andresa Casamayor de La Coma."
Spain's News Spanish News in English.  "The Numbers of an Advanced."