Beyer, Hugh. Contextual design : defining customer-centered systems / Hugh Beyer, Karen Holtzblatt. - San Francisco, Calif. : Morgan Kaufmann, 1998. - xxiii, 472 p. : ill. ; 24 cm. Includes bibliographical references (p. [449]-457) and index. ISBN: 1558604111 RM18.070 LCCN: 97-035927 Subjects--Topical Terms: System design.System analysis.