Ryan, D. (2012). Understanding Digital Marketing (2nd.). Kogan Page.
Cita Chicago (17th ed.)Ryan, Damian. Understanding Digital Marketing. 2nd. Kogan Page, 2012.
Cita MLA (9th ed.)Ryan, Damian. Understanding Digital Marketing. 2nd. Kogan Page, 2012.
Atenció: Aquestes cites poden no estar 100% correctes.