Cita APA

Roberts, L., & Lorena Roberts. (2001). Happy Street: Teacher's book. Oxford,New York: Oxford University Press.

Chicago Style Citation

Roberts, Lorena, i Lorena Roberts. Happy Street: Teacher's Book. Oxford,New York: Oxford University Press, 2001.

Cita MLA

Roberts, Lorena, i Lorena Roberts. Happy Street: Teacher's Book. Oxford,New York: Oxford University Press, 2001.