Cita APA (7th ed.)

Tupas, T. R. F. (1997). Second language teaching. University of the Philippines Open University.

Cita Chicago (17th ed.)

Tupas, T. Ruanni F. Second Language Teaching. Los Banos, Laguna: University of the Philippines Open University, 1997.

Cita MLA (9th ed.)

Tupas, T. Ruanni F. Second Language Teaching. University of the Philippines Open University, 1997.