“Implementation of Total Quality Management (TQM) and Six Sigma in the Learning Process in Vocational High Schools: Implementasi Total Quality Manajemen (TQM) dan Six Sigma dalam Proses Pembelajaran di Sekolah Menengah Kejuruan” (2022) Indonesian Journal of Education Methods Development, 17(3), p. 10.21070/ijemd.v19i.652. doi:10.21070/ijemd.v19i.652.