Inferno1976
by Jerry Pournelle
From back cover Pocket paperback May 1976:
INTO THE FANTASTIC ABYSS OF AN INGENIOUS, LIVING HELL
An unearthly voice hisses unholy welcome. And the late, great Allen Carpentier begins his one-way journey into the dim nether regions where flame-colored demons wield diabolically sharp pitchforks and tormented vixens reign forever in a pond of sheer ice. Here, in this land of torment and terror, he discovers the amazing truth of the ultimate adventure that lies beyond the grave.
— from OpenLibrary
14 editions at OpenLibrary