Friendly, M., & Friendly, M. (1991). SAS system for statistical graphics (1. edition.). U.S.A.: SAS Institute.
Citación estilo ChicagoFriendly, Michael, y Michael Friendly. SAS System for Statistical Graphics. 1. edition. U.S.A.: SAS Institute, 1991.
Cita MLAFriendly, Michael, y Michael Friendly. SAS System for Statistical Graphics. 1. edition. U.S.A.: SAS Institute, 1991.
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