Cita APA (7th ed.)

Krashen, S. D. (1984). Writing: Research, theroy and applications. Pergamon Institute of English.

Cita Chicago (17th ed.)

Krashen, Stphen D. Writing: Research, Theroy and Applications. Oxford: Pergamon Institute of English, 1984.

Cita MLA (9th ed.)

Krashen, Stphen D. Writing: Research, Theroy and Applications. Pergamon Institute of English, 1984.