Erdősi, Szilvia. “Pontatlan Adatok - Joseph W. Duncan & A. C. Gross: Statistics for the 21st Century, Irwin, 1995”. The Hungarian Journal of Marketing and Management, vol. 30, no. 3, Dec. 2019, pp. 59-60, https://journals.lib.pte.hu/index.php/mm/article/view/2394.