Writing as: Bob Powell, S. R. Powell
According to Wikipedia: "Bob Powell, (né Stanley Robert Pawlowski) was an American comic book artist known for his work during the 1930-1940s Golden Age of comic books, including on the features "Sheena, Queen of the Jungle" and "Mr. Mystic". He received a belated credit in 1999 for co-writing the debut of the popular feature "Blackhawk". Powell also did the pencil art for the bubble gum trading card series Mars Attacks. He officially changed his name to S. Robert Powell in 1943.
According to Lambiek's Comiclopedia: "Bob Powell was an artist who was mainly active during the Golden Age of American comics. Born in 1916 as Stanley Robert Pawlowski, he attended the Pratt Institute in New York City, and went to work for the Eisner-Iger studios in the late 1930s. He worked for many companies through this studios, like Fiction House (Jumbo Comics), Fox (Wonderworld Comics, Mystery Men Comics), and Harvey ('Ted Parrish' in Speed Comics), Timely, Quality (Crack Comics, Hit Comics, Military Comics, Smash Comics, Feature Comics)."