Book excerpt: Archaeologist Keyser and Klassen share with readers the origins, diversity, and beauty of Plains rock art, with the hope of encouraging greater awareness and respect for this cultural tradition by society as a whole. Their guide covers the natural and archaeological history of the northwestern Plains; explains rock art forms, techniques, styles, terminology and dating; and suggests interpretations of images and compositions. The text is illustrated throughout with black-and-white photos, maps and drawings. The writing is serious, but accessible to the general reader. c. Book News Inc.