Enge, E., Spencer, S., & Stricchiola, J. C. (2015). The Art of SEO: Mastering search engine optimazion (Third Edition.). O'Reilly.
Cita Chicago Style (17a ed.)Enge, Eric, Stephan Spencer, y Jessie C. Stricchiola. The Art of SEO: Mastering Search Engine Optimazion. Third Edition. Beijing: O'Reilly, 2015.
Cita MLA (9a ed.)Enge, Eric, et al. The Art of SEO: Mastering Search Engine Optimazion. Third Edition. O'Reilly, 2015.
Precaución: Estas citas no son 100% exactas.