A Visual History of Digit Books 1956-1967 (7)
1957 Digit N.N
The Man From Thunder River Dave Waldo
1957 Digit Books N.N.
Warbonnet Dave Waldo
1957 Digit Books N.N.
Appointment in Hell Vernon Warren
1957 Digit Books N.N.
The Man From Thunder River Dave Waldo
1957 Digit Books N.N.
Warbonnet Dave Waldo
1957 Digit Books N.N.
Appointment in Hell Vernon Warren
1957 Digit Books N.N.
Brandon Returns Vernon Warren
1957 Digit N.N.
Brandon in New York Vernon Warren
1957 Digit Books N.N.
Brandon Takes Over Vernon Warren
1957 Digit Books N.N.
No Bouquets For Brandon Vernon Warren
1957 Digit Books N.N.
Japanese Bondage George Frederick Whiting
Digit Books N.N.
I Stole $16,000,000 Herbert Emerson Wilson
1957 Digit Books N.N.
Four Fathoms Deep John Wilson
1957 Digit Books N.N.
Guns of Greed H.A. Woodbury
Digit Books N.N.

Gold Rush City H A Woodbury
1957 Digit N.N.
Lion Rampant Robert Woollcombe
1957 Digit Books N.N.
Shame Emile Zola
1958 Digit Books N.N.
I Came Back Krystyna Zywulska
1957 Digit Books N.N.
Other possibles that I have not come across yet:
Phillips Gerald Rustler's Rule 1957
Waldo Dave Ride On Stranger 1957
As far as I am aware this is not a complete list could be other possibilities.