Nguyen Xuan, Sang, 		Minh Quan, Nguyen, 		Huu Tho, Nguyen, 		Thi Thanh Thuy Mai, Le, AND 		Van Cuu, Ho.
" Crystalline Structure, Optical Properties and Photocatalytic Activity of Cr3+-Doped ZnO Nanoparticles" <em>VNU Journal of Science: Natural Sciences and Technology</em> [Online], Volume 34 Number 4 (23 December 2018)