Nguyen Duc Son, Nguyen Duc Anh and Le Minh Nguyet (2026) “THE CURRENT STATUS OF MATHEMATICAL COMPETENCY AMONG GRADE 9 STUDENTS FROM SIX SECONDARY SCHOOLS IN HO CHI MINH CITY”, HNUE Journal of Science: Journal of Educational Science, 71(6), pp. 107–117. doi:10.18173/2354-1075.2026-%x.