Cita APA (7a ed.)

Maidment, S., & Roberts, L. (2003). Happy street: Activity book 1 (7a. ed.). Oxford University.

Cita Chicago Style (17a ed.)

Maidment, Stella, y Lorena Roberts. Happy Street: Activity Book 1. 7a. ed. Oxford: Oxford University, 2003.

Cita MLA (8a ed.)

Maidment, Stella, y Lorena Roberts. Happy Street: Activity Book 1. 7a. ed. Oxford University, 2003.