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Here are the books Watterson put out of Calvin and Hobbes:

Calvin and Hobbes (1987)
Something Under the Bed is Drooling (1988)
The Essential Calvin and Hobbes (1988)
Yukon Ho! (1989)
The Calvin and Hobbes Lazy Sunday Book (1989)
Weirdos From Another Planet! (1990)
The Authoritive Calvin and Hobbes (1990)
Scientific Progress Goes "Boink" (1991)
Revenge of the Baby-Sat (1991)
The Indespensable Calvin and Hobbes (1992)
Attack of the Deranged Mutant Killer Monster Snow Goons (1992)
The Days Are Just Packed (1993)
Homicidal Psycho Jungle Cat (1994)
The Calvin and Hobbes Tenth Anniversary Book (1995)
There's Treasure Everywhere (1996)
It's A Magical World (1996)
Calvin and Hobbes: Sunday Pages 1985-1995 (2001)



The Complete Calvin and Hobbes

In October 2005, Andrews & McBeel released a collection of every Calvin and Hobbes comic strip, "The Complete Calvin and Hobbes". It's 3 books, 1440 pages long, and contains new pictures, information, etc.



Warner once published a miniseries consisting of three small books. (Thereby Hangs A Tail, One Day The Wind Will Change, and In The Shadow of the Night. Personally, I've seen better names for a C&H book.) They each contain strips from Calvin and Hobbes. Here they are, and at this age, I think you can only buy them off internet auctions.