APA (7e ed.) Bronvermelding

Robles, F. C. (1985). Developing English proficiency in college, book 2: Instructional material for English 2 Intermediate Communication Skills. Goodwill Trading Co.

Chicago (17e ed.) Bronvermelding

Robles, Felicidad C. Developing English Proficiency in College, Book 2: Instructional Material for English 2 Intermediate Communication Skills. Manila: Goodwill Trading Co, 1985.

MLA (9e ed.) Bronvermelding

Robles, Felicidad C. Developing English Proficiency in College, Book 2: Instructional Material for English 2 Intermediate Communication Skills. Goodwill Trading Co, 1985.