S. S. Georgievska, “REDUCTION OF A BOUNDARY PROBLEM OF THE THIRD ORDER TO A BOUNDARY PROBLEM OF THE SECOND ORDER”, Mat. Bilt., vol. 18, no. 1, pp. 87–92, Jan. 1994, Accessed: Nov. 03, 2026. Available: https://bilten.smm.org.mk/index.php/bilten/article/view/1520