Here are the comics from March 12, 1939, as they appeared in the Dayton Daily News. It's not quite complete (one page claims 20 pages of comics; we've only got 12 here, and three of those are ads), but it's most of it (if they're counting drawn ads as comics).
We've got Captain Easy by Roy Crane, Flash Gordon by Alex Raymond, Don Winslow of the Navy by Lieut. Comdr. F. V. Martinek, U.S.N.R., Bos'n Hal, Sea Scout by Leut. Comdr. F. V. Martinek, U.S.N.R. (DDN seems to have misspelled the abbreviation for Lieutenant in Sea Scout...), Boots by Martin, Dan Dunn Secret perative by Norman Marsh, Li'l Abner by Al Capp, an ad for Beech-Nut gum, the Three Musketeers by someone whose name I can't read but who might well be J. Carroll Mansfield, Highlights of History by J. Carroll Mansfield, an ad for dinnerware form May & Company (see Mary Livingston), Mickey Finn by Lank Leonard, Toonerville Folks by Fontaine Fox, and an ad for some kind of viewmaster type deal from Cocomalt called "Novel-Viewer".
Boots is incredibly stilted and unfunny, but you get to see her upper thigh...
You can buy this section (not from me) at