Coincidentally or not, Alex Toth left Sierra Smith at the same time as Millard; the strip continued (under others including artist Al Ulmer) for the run of the comic, missing #20 and the final issue, #24, as the page count dropped. The Detective reprint credits Frank Giacoia as inker on the first Sierra; some more Sierra stories signed solely by Toth may be inked by others as well.
Although this list merely confirms guesses at the authorship of the Sierra Smith series beyond the first story, it leads into my next post on another Joe Millard series.
Sierra Smith, Western Detective in Dale Evans Comics
written by Joe Millard, pencilled by Alex Toth
|S-O/48||#1||The Case of the Terrified Tenderfoot|
|N-D/||#2||The Case of the Battered Balloonist|
|J-F/49||#3||The Case of the Perfumed Plunder|
|M-A/||#4||The Case of the Outlawed Outlaw|
|M-J/||#5||The Case of the Forgotten Stagecoach|
|J-A/||#6||Case of the Colossal Fossil|
|S-O/||#7||Case of the Teetering Tower|
|N-D/||#8||The Case of the Five-Cent Fortune|
|J-F/50||#9||The Case of the Haunted Horse|
|M-A/||#10||The Case of the Oily Worm|
|M-J/||#11||The Case of the Furious Fiddler|