Nelfuad, N., S. Hardhienata, and S. Setyaningsih. “Modeling and Optimization Teacher Work Innovation : An Empirical Study Using POP-SDM Approach on Vocational Teachers of Private Vocational Schools in Depok”. Journal of Industrial Engineering & Management Research, Vol. 2, no. 4, June 2021, pp. 92 - 106, doi:10.7777/jiemar.v2i4.166.