HAN, Pham Van et al.
 “BRAINballs” educational balls - An innovative teaching method in education "Children learn while playing".
<strong>VNU Journal of Science: Education Research</strong>, [S.l.], v. 36, n. 4, nov. 2020.
ISSN 2588-1159.
Available at: &lt;<a href="https://js.vnu.edu.vn/ER/article/view/4443" target="_new">https://js.vnu.edu.vn/ER/article/view/4443</a>&gt;. Date accessed: 24 apr. 2024.
doi: <a href="https://doi.org/10.25073/2588-1159/vnuer.4443">https://doi.org/10.25073/2588-1159/vnuer.4443</a>.