Situmorang, B. (2014). The Effect of Instructional Leadership, Knowledge of Educational Management, Interpersonal Communication and Job Satisfaction to Organization Commitment of the Senior High School Principals (A Case Study in Senior High Schools in Medan Municipality). International Journal of Sciences: Basic and Applied Research (IJSBAR), 18(1), 234–253. Retrieved from https://gssrr.org/index.php/JournalOfBasicAndApplied/article/view/2700