Crawley, M. J. (2007). The R book. John Wiley.
Cita Chicago (17th ed.)Crawley, Michael J. The R Book. Londres: John Wiley, 2007.
Cita MLA (9th ed.)Crawley, Michael J. The R Book. John Wiley, 2007.
Atenció: Aquestes cites poden no estar 100% correctes.