1. Master of Administrative Science, University of HKBP Nommensen, Jl. Perintis Kemerdekaan, No. 23, Medan, Indonesia
2. Master of Management, University of HKBP Nommensen, Jl. Perintis Kemerdekaan, No. 23, Medan, Indonesia
3. Management Program, Faculty of Economics and Business, University of HKBP Nommensen, Jl. Sutomo, No. 4, Medan, Indonesia
4. Department of Business Administration, College of Management, Chaoyang University of Technology, Taichung, Taiwan