Cita APA (7a ed.)

Eckersley, C. E., & Eckersley, J. M. (1972). Essential English for foreign students: [Students' book] . Book one (New impression.). Longman.

Cita Chicago Style (17a ed.)

Eckersley, C. E., y John Macaulay Eckersley. Essential English for Foreign Students: [Students' Book] . Book One. New impression. London: Longman, 1972.

Cita MLA (9a ed.)

Eckersley, C. E., y John Macaulay Eckersley. Essential English for Foreign Students: [Students' Book] . Book One. New impression. Longman, 1972.