DUANGPHACHANH, P. “Guidelines For Developing 21St Century Skills for Administrators in Secondary Schools of Shikhodttabong District, Vientiane Capital”. Souphanouvong University Journal Multidisciplinary Research and Development, vol. 12, no. Fast Track, Sept. 2026, pp. 348-55, doi:10.69692/SUJMRD1203F348.