Cita APA (7a ed.)

Grappone, J., & Couzin, G. (2008). Search engine optimization: An hour a day (2nd ed.). Wiley Pub..

Cita Chicago Style (17a ed.)

Grappone, Jennifer, y Gradiva Couzin. Search Engine Optimization: An Hour a Day. 2nd ed. Indianapolis, Ind.: Wiley Pub., 2008.

Cita MLA (8a ed.)

Grappone, Jennifer, y Gradiva Couzin. Search Engine Optimization: An Hour a Day. 2nd ed. Wiley Pub., 2008.