Mattson, D. E. (1981). Statistics: Difficult concepts, understandable explanations. Mosby.
Cita Chicago (17th ed.)Mattson, Dale E. Statistics: Difficult Concepts, Understandable Explanations. St. Louis: Mosby, 1981.
Cita MLA (9th ed.)Mattson, Dale E. Statistics: Difficult Concepts, Understandable Explanations. Mosby, 1981.
Atenció: Aquestes cites poden no estar 100% correctes.