Cita APA

Phillips, D., & Sheerin, S. (1990). Signature _: Teacher?s book. NelSon, U.K: [s.n].

Citación estilo Chicago

Phillips, Diane, and Susan Sheerin. Signature _: Teacher?s Book. NelSon, U.K: [s.n], 1990.

Cita MLA

Phillips, Diane, and Susan Sheerin. Signature _: Teacher?s Book. NelSon, U.K: [s.n], 1990.