Cita APA (7th ed.)
Eckersley, C. E. (1951). Essential english: Book one. Longman.
Cita Chicago (17th ed.)
Eckersley, C. E. Essential English: Book One. London: Longman, 1951.
Cita MLA (9th ed.)
Eckersley, C. E. Essential English: Book One. Longman, 1951.
Atenció: Aquestes cites poden no estar 100% correctes.