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Prolog Programming 
Prolog Programming: A First Course (Paul Brna) [Mirror] [PDF]
Learn Prolog Now! (Patrick Blackburn, et al) Building Expert Systems In Prolog (Amzi)
Logic, Programming and Prolog, 2nd Edition (Ulf Nilsson/Jan Maluszynski)
Artificial Intelligence through Prolog (Neil Rowe) [Source] An Introduction to Logic Programming through Prolog
Artificial Intelligence and Logic Programming Books Adventure in Prolog (Amzi)
Prolog and Natural-Language Analysis (Fernando Pereira/Stuart M. Shieber)
Natural Language Processing in Prolog (Gerald Gazdar/Chris Mellish)