Welch, B. L. (1947). "The generalization of "Student's" problem when several different population variances are involved". Biometrika. 34 (1–2). ss. 28-35. doi:10.1093/biomet/34.1-2.28. MR0019277.
Welch, B. L. (1947). "The generalization of "Student's" problem when several different population variances are involved". Biometrika. 34 (1–2). ss. 28-35. doi:10.1093/biomet/34.1-2.28. MR0019277.
Ruxton, G. D. (2006). "The unequal variance t-test is an underused alternative to Student's t-test and the Mann–Whitney U test". Behavioral Ecology. Cilt 17. ss. 688-690. doi:10.1093/beheco/ark016.
Fagerland, M. W. (2012). "t-tests, non-parametric tests, and large studies—a paradox of statistical practice?". BioMed Central Medical Research Methodology. Cilt 12. s. 78. doi:10.1186/1471-2288-12-78.