Hakim, J., M. Matin, and S. Supadi. “ANALYSIS OF THE EFFECT OF KOHESIVITAS GROUPS AND EFFECTIVENESS OF TEACHER WORK PRODUCTIVITY”. IJER - INDONESIAN JOURNAL OF EDUCATIONAL REVIEW, Vol. 5, no. 1, Sept. 2018, pp. 183-90, doi:10.21009/IJER.05.01.20.