Cita APA

(1981). World English: Workbook. Washington, DC.: United states Department of state.

Chicago Style Citation

World English: Workbook. Washington, DC.: United states Department of state, 1981.

Cita MLA

World English: Workbook. Washington, DC.: United states Department of state, 1981.

Atenció: Aquestes cites poden no estar 100% correctes.