Lungton, R. C. (1986). American topics: A reading-vocabulary text for speakers of English as a second language (2a. ed.). Prentice Hall Regents.
Citazione stile Chigago Style (17a edizione)Lungton, Robert C. American Topics: A Reading-vocabulary Text for Speakers of English as a Second Language. 2a. ed. Englewood Cliffs: Prentice Hall Regents, 1986.
Citatione MLA (9a ed.)Lungton, Robert C. American Topics: A Reading-vocabulary Text for Speakers of English as a Second Language. 2a. ed. Prentice Hall Regents, 1986.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.