Vaynerchuk, G. (2011). The thank you economy. New York: Harper Business.
Chicago Style aipamenaVaynerchuk, Gary. The Thank You Economy. New York: Harper Business, 2011.
MLA aipamenaVaynerchuk, Gary. The Thank You Economy. New York: Harper Business, 2011.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.