PYO, YONG-SOO, and YONG-TAE SHIN. “ON THE TOTAL CURVATURE OF SURFACES IMMERSED IN EUCLIDEAN SPACES OF DIMENSION HIGHER THAN FOUR”. Tamkang Journal of Mathematics 22, no. 2 (June 1, 1991): 113–122. Accessed May 19, 2024. https://journals.math.tku.edu.tw/index.php/TKJM/article/view/4581.