25832 William Cochran: The chi-square test of goodness of fit.
Ann. Math. Stat. 23 (1952), 315-345.

25120 Wikipedia: Chi-square test. Internet 2014, 29p.

25121 Wikipedia: Chiquadrat-Test. Internet 2014, 29p.

25122 Wikipedia: Test chiquadrato. Internet 2014, 8p.