Nikolov, G., and R. Uluchev. “ESTIMATES FOR THE BEST CONSTANT IN A MARKOV $L_2$–INEQUALITY WITH THE ASSISTANCE OF COMPUTER ALGEBRA”. Ann. Sofia Univ. Fac. Math. And Inf., vol. 104, Dec. 2017, pp. 55-75, https://ftl5.uni-sofia.bg./index.php/fmi/article/view/37.