Mark Of The Cobra

Two-Book Detective Magazine - November 1934

Also, The Death Bus and Nightmare Isle

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C.O.D. — Cash Or Death

Star Detective August 1937

Also featuring Gunman’s Alibi, Armed Legs, and G-Man Wanted

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Murder, More Or Less

Complete Detective 1939 October

Cover reused from Star Detective

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Ghouls In Modern Dress

Dime Mystery Magazine - October 1939

Also, The Test-Tube Murders

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Last Call For Murder!

Ten Detective Aces August 1937

The seller lists this as a Saunders cover, but I am skeptical.

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The Mystery of The Red Robe

Thrillig Detective November 1939

A Novel Of Murder At The Race Track

Also, The Spiders And The Fly and Masquerade For Crime

via Gregory Urbach