Kujumdžieva-Nikoloska, Marija, and Dragan Dimitrovski. 1993. “NEW FORMULAR FOR APPROXIMATE SOLUTIONS OF THE LINEAR DIFFERENTIAL EQUATIONS OF THE II AND III ORDER”. Matematichki Bilten 17 (1): 83-92. https://bilten.smm.org.mk/index.php/bilten/article/view/1503.