Ryzhov , Y.M. (1988) “Limited theorem for random functions, plotted according to quadratic forms from Gaussian random values”, Ukrains’kyi Matematychnyi Zhurnal, 40(4), pp. 487–493. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/9184 (Accessed: 17 February 2026).