APA Style

WILSON, E, L., HABIBULLAH, A. (1989). SAP90 : a series of computer programs for the static and dynamic finite element analysis of structures user's manual . California: Computers & Structures.

MLA Style

WILSON, EDWARD, L.., HABIBULLAH, ASHRAF. "SAP90 : a series of computer programs for the static and dynamic finite element analysis of structures user's manual". California: Computers & Structures, 1989. Text.