Cita APA (7a ed.)

Villarroel, M., & Charrington, M. R. (1998). Eko and friends: Teacher's guide (1ª ed.).

Cita Chicago Style (17a ed.)

Villarroel, Magaly, y Mary Rotonda Charrington. Eko and Friends: Teacher's Guide. 1ª ed. Edinburgh, 1998.

Cita MLA (9a ed.)

Villarroel, Magaly, y Mary Rotonda Charrington. Eko and Friends: Teacher's Guide. 1ª ed. 1998.