Richards, J. C. Interchange. English for international communication. Student´s book 1 (20a ed.).
Citazione stile Chigago Style (17a edizione)Richards, Jack C. Interchange. English for International Communication. Student´s Book 1. 20a ed.
Citatione MLA (8a ed.)Richards, Jack C. Interchange. English for International Communication. Student´s Book 1. 20a ed.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.