At the Narrow Passage
by Richard C. Meredith (G. P. Putnam’s Sons, 1973)
Forty years before Pratchett and Baxter’s ‘The Long Earth’, the multiverse played host to Richard C. Meredith’s Timeliners Trilogy – pulpy, engaging, alternative SF military history with aliens and gratuitously accommodating females thrown in (this objectification undermining what had been a promising start).