Examples of Mulford's art are below. They vary in quality, the pulp art being the lowest. Perhaps because the pay was poor he put less time into those pieces. Judging from the examples below, he seems to have done his best work during the mid-1920s.
There is one outstanding illustration that he never came close to equaling, so far as I can tell at present. Sort of like the novelist who has only one great book. You'll find it at the bottom of the scroll.
An example of Mulford's pulp magazine cover art.
Probably painted a couple months after the Pearl Harbor attack. At that time, the only major encounter between the American and Japanese armies was in the Philippines, on Bataan Peninsula.
This is a fine illustration. In my opinion, only the Delineator cover art and the American story illustration come close -- but not very close. I wonder why Mulford wasn't able to consistently do this well.