Herzel, Amato. “Multivariate Moments and Products of Moments: Derivation of Expectations and Estimators from Univariate Formulae in Simple Random Sampling”. Statistica 47, no. 1 (January 1, 1987): 3–27. Accessed November 24, 2024. https://rivista-statistica.unibo.it/article/view/728.