Flynn, Laurie (14 de septiembre de 1998). «Online City Guides Compete in Crowded Field». En The New York Times, ed. The New York Times on the web. Consultado el 4 de abril de 2020.
Strauss, Neil (15 de noviembre de 2017). «Elon Musk: The Architect of Tomorrow». Rolling Stone. Consultado el 15 de noviembre de 2017. «One thing he claims is he gave us a whole bunch of money to start, my brother and I, to start up our first company [Zip2, which provided online city guides to newspapers]. This is not true," Musk says. "He was irrelevant. He paid nothing for college. My brother and I paid for college through scholarships, loans and working two jobs simultaneously. The funding we raised for our first company came from a small group of random angel investors in Silicon Valley.»
