Keller, G. (2005). Statistics for management and economics (7th ed.). Thomson/Brooks/Cole.
Cita Chicago (17th ed.)Keller, Gerald. Statistics for Management and Economics. 7th ed. Belmont, Calif: Thomson/Brooks/Cole, 2005.
Cita MLA (9th ed.)Keller, Gerald. Statistics for Management and Economics. 7th ed. Thomson/Brooks/Cole, 2005.
Atenció: Aquestes cites poden no estar 100% correctes.