The on-sale date is the publication date reported in the U. S. Copyright Office filing.
Writer credit revised from Joe Devlin to ? by Craig Delich 2013-4-6. Devlin did not write this strip according to the Who's Who. Artist correction from Joe (who did not exist) to John Devlin also made by Craig Delich.
The writer credit for Gustavson have been replaced with ? (notes added by Craig Delich 2013-1-23, revised 2017-2-23). Jim Amash and Mike Kooiman, in the Quality Companion, verify that Gustavson wrote this feature through Police #22, then picked up again with #37. The intervening writer is unknown for this story.
Art credits restored and lettering credit added by Craig Delich, courtesy of Terry Gustafson, son of Paul Gustavson.