John Powers Severin (December 26, 1921 – February 12, 2012) was an American comics artist noted for his distinctive work with EC Comics, primarily on the war comics "Two-Fisted Tales" and "Frontline Combat"; for Marvel Comics, especially its war and Western comics; and for his 45-year stint with the satiric magazine "Cracked". He was one of the founding cartoonists of "Mad" in 1952.
John Powers Severin was not the only founding cartoonist of "Mad".
It says that he was "one of" the founding cartoonists, which necessitates others, which means he was not the only one.