Simpson's Paradox: References

Appleton, D. R., French, J. M., and Vanderpump, M. P. J.
Ignoring a covariate: an example of Simpson's Paradox. The American Statistician 50 (1996) 340-341.

PJ Bickel, EA Hammel, and JW O'Connell.
Sex bias in graduate admissions: data from Berkeley. Science 187 (1975), 398-404.

Morrell, C.H.
Simpson's Paradox: an example from a longitudinal study in South Africa. Journal of Statistics Education 7(3) (1999)

Simpson, E. H.
The interpretation of interaction in contingency tables. Journal of the Royal Statistical Society, Series B 13 (1951) 238-241.

Wagner, C.H.
Simpson's Paradox in real life. The American Statistician 1982.

Westbrooke, I.
Simpson's Paradox: An example in a New Zealand survey of jury composition. Chance 11(2) (1998) 40-42.