Bekar M, Hathout F, Yayli Y. Legendre curves and the singularities of ruled surfaces obtained by using rotation minimizing frame. Ukr. Mat. Zhurn. [Internet]. 2021 May 24 [cited 2025 Apr. 7];73(5):589-601. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/895