The on-sale date is from the publication date recorded in the Catalog of Copyright Entries, Part 2, Periodicals, 1941, New Series, Vol. 36, No. 2.
Note 1: George "Inky" Roussos is based on the artist of the same name, and Blackie Biro is based on writer / artist Charles Biro.
Note 2: In the story this is said:
"Hey, Niles! this is a panic! have a look at this strip in the Star "Crime Takes
This refers to the Red Comet story in Planet Comics (Fiction House, 1940 series) #5, May 1940.