Who was the founder of the sports league Mirtha Marrero played in?
Mirtha Marrero Mirtha Marrero [Fernández] is a former pitcher who played from 1948 through 1953 in the All-American Girls Professional Baseball League. She batted and threw right handed.
Leo Seltzer Leo A. Seltzer (April 5, 1903 – January 30, 1978) is generally credited as the creator of the sport of roller derby, and was the founder and head of the original Roller Derby league from 1935 until his son Jerry Seltzer took over the business in 1958.