Cita APA (7a ed.)

Ziefert, H., & Demarest, C. L. (1999). I need a valentine!: A lift-the-flap story. Little Simon.

Cita Chicago Style (17a ed.)

Ziefert, Harriet, y Chris L. Demarest. I Need a Valentine!: A Lift-the-flap Story. New York, N.Y.: Little Simon, 1999.

Cita MLA (8a ed.)

Ziefert, Harriet, y Chris L. Demarest. I Need a Valentine!: A Lift-the-flap Story. Little Simon, 1999.