APA citiranje

Robinson, B. (1989). Answer key for workbook to accompany focus: An ESL grammar. New York: St. Martin's Press.

Trích dẫn kiểu Chicago

Robinson, Barbara. Answer Key for Workbook to Accompany Focus: An ESL Grammar. New York: St. Martin's Press, 1989.

MLA citiranje

Robinson, Barbara. Answer Key for Workbook to Accompany Focus: An ESL Grammar. New York: St. Martin's Press, 1989.