Beyer, H., & Holtzblatt, K. (1998). Contextual design: Defining customer-centered systems. Morgan Kaufmann.
Chicago Style aipamenaBeyer, Hugh, and Karen Holtzblatt. Contextual Design: Defining Customer-centered Systems. San Francisco, California: Morgan Kaufmann, 1998.
MLA aipamenaBeyer, Hugh, and Karen Holtzblatt. Contextual Design: Defining Customer-centered Systems. Morgan Kaufmann, 1998.
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