Cita APA (7a ed.)

Howard-Williams, D., Tomalin, M., & Watcyn-Jones, P. Instant lessons 1. Elementary.

Cita Chicago Style (17a ed.)

Howard-Williams, Deirdre, Mary Tomalin, y Peter Watcyn-Jones. Instant Lessons 1. Elementary.

Cita MLA (8a ed.)

Howard-Williams, Deirdre, et al. Instant Lessons 1. Elementary.