Cita APA (7a ed.)

Ogundipe P. A. & Tregidgo P. S. (1974). Practical English: A comprehensive secondary course. Book four. Longman.

Cita Chicago Style (17a ed.)

Ogundipe P. A. y Tregidgo P. S. Practical English: A Comprehensive Secondary Course. Book Four. England: Longman, 1974.

Cita MLA (9a ed.)

Ogundipe P. A. y Tregidgo P. S. Practical English: A Comprehensive Secondary Course. Book Four. Longman, 1974.