Gaya APA

WALVOORD, B, E. (1988). Three steps to revising your writing for style, grammar, puctuation, and spelling . London: Scott, Foresman and Company.

Gaya MLA

WALVOORD, Barbara, E. "Three steps to revising your writing for style, grammar, puctuation, and spelling". London: Scott, Foresman and Company, 1988. UMUM.