BƯỜNG, Lê Ngọc.
 Khái Niệm (G, e, ô ) - Đầy Đủ.
<strong>VNU Journal of Science: Natural Sciences and Technology</strong>, [S.l.], v. 3, n. 3, sep. 1987.
ISSN 2588-1140.
Available at: &lt;<a href="https://js.vnu.edu.vn/NST/article/view/3951" target="_new">https://js.vnu.edu.vn/NST/article/view/3951</a>&gt;. Date accessed: 24 nov. 2024.