Crypt-City of the Deathless One

Caliban's War: Book 2 of the Expanse (now a Prime Original series)

Asteroid of Fear

Assignment on Venus

Leviathan Wakes: Book 1 of the Expanse (now a Prime Original series)

Lost Sci-Fi Books 1 thru 10

Nine Sci-fi Stories (Unabridged): optional

Star Ship (Unabridged)

Nemesis Games: Book 5 of the Expanse (now a Prime Original series)

The Chapter Ends

Poul Anderson: Snowball

Abaddon's Gate: Book 3 of the Expanse (now a Prime Original series)

Black Amazon of Mars

Cibola Burn: Book 4 of the Expanse (now a Prime Original series)

And The Gods Laughed

Valley of Dreams