First read of Barrington Bayley's work.
The Fall of Chronopolis - Interesting ideas regarding time travel, with an imperial time corps at war with a future society. Basically ignores time travel paradoxes by having history repeating with the changes made. Unsure how original his ideas were, but the first time I'd quite read anything like it. Interesting enough plot to go along with the premise with a couple of interesting characters, but the majority stuck to the generic religious zealot that the society had become.

Collision with Chronos - Another time-travel story which has nothing in common with the other story. Earth is basically run by a society of nazis obsessed with racial purity. Hard to find any particularly likable characters in this story, but again follows a reasonable plot and has probably more sophisticated ideas about how time works.
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