MLA

Townsend, Carl. Mastering Excel On the Ibm Pc. San Francisco (Calif.): Sybex, 1988.

APA

Townsend, C. (1988). Mastering Excel on the IBM PC. San Francisco (Calif.): Sybex.

Chicago

Townsend, Carl, Mastering Excel On the IBM PC. San Francisco (Calif.): Sybex, 1988.