I read this a few years ago, and liked it so much I decided to pick up the hardback first.
Piper, H. Beam. Lord Kalvan of Otherwhen. Garland Publishing, 1975. First hardback edition, a Fine copy, sans dust jacket, as issued. Novel of a modern day state trooper accidentally sucked into an alternate timeline where he uses his knowledge of military tactics and technology (such as the composition of gunpowder) to topple a corrupt theocracy. Part of the Garland Library of Science Fiction, reprinted from slightly blown-up pages from the Ace paperback original. Supplements a PBO first. Bought for £68 plus shipping from a UK seller.
Tags: Books, Garland Press, H. Beam Piper, Science Fiction