There s no clear signature for the cover artwork of the Bantam edition of The Polar Treasure. The HTC would like you to consider Frank McCarthy.
Frank McCarthy (March 30, 1924 — November 17, 2002) painted illustrations, advertisements, film posters, and book covers. He painted numerous covers from 1948 to 1993. While many have put forward either Lou Feck or James Avati as the artist for the Bantam Doc Savage novel The Polar Treasure, I currently feel McCarthy is the best candidate.
(Click either to enlarge)