Lê Thiếu, Tráng. “EXTENDING SOME RESULTS OF FLAT GEOMETRY WHEN SOLVING SPATIAL GEOMETRY”. SCIENTIFIC JOURNAL OF TAN TRAO UNIVERSITY 7, no. 21 (August 17, 2021). Accessed November 23, 2024. https://tckh.daihoctantrao.edu.vn/index.php/sjttu/article/view/510.