Bukor, Jozsef, Péter Filakovszky, and János T. Tóth. 1998. “On the Diophantine Equation x_1x_2···x_n = h(n)(x_1 + x_2 +. + x_n)”. Annales Mathematicae Silesianae 12 (September):123-30. https://journals.us.edu.pl/index.php/AMSIL/article/view/14169.