Cita APA (7a ed.)

Sierra, J., & Sweet, M. (2009). The sleepy little alphabet: A bedtime story from Alphabet Town. Alfred A. Knopf.

Cita Chicago Style (17a ed.)

Sierra, Judy, y Melissa Sweet. The Sleepy Little Alphabet: A Bedtime Story from Alphabet Town. New York: Alfred A. Knopf, 2009.

Cita MLA (8a ed.)

Sierra, Judy, y Melissa Sweet. The Sleepy Little Alphabet: A Bedtime Story from Alphabet Town. Alfred A. Knopf, 2009.