Jantsch, J. (2010). Referral engine: Teaching your business to market itself. Portofolio.
Chicago-referens (17:e uppl.)Jantsch, John. Referral Engine: Teaching Your Business to Market Itself. London: Portofolio, 2010.
MLA-referens (9:e uppl.)Jantsch, John. Referral Engine: Teaching Your Business to Market Itself. Portofolio, 2010.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.