Nguyen Duc Son, Nguyen Duc Anh, and Le Minh Nguyet, “THE CURRENT STATUS OF MATHEMATICAL COMPETENCY AMONG GRADE 9 STUDENTS FROM SIX SECONDARY SCHOOLS IN HO CHI MINH CITY”, HNUE JoES, vol. 71, no. 6, pp. 107–117, Oct. 2026, doi: 10.18173/2354-1075.2026-%x.