Cita APA (7a ed.)

(1968). Progress to Vantage: Workbook (with key). Summertown Publishing.

Cita Chicago Style (17a ed.)

Progress to Vantage: Workbook (with Key). Summertown: Summertown Publishing, 1968.

Cita MLA (9a ed.)

Progress to Vantage: Workbook (with Key). Summertown Publishing, 1968.