1. Graduate School, Master of Management Program, University of HKBP Nommensen, Jl. Perintis Kemerdekaan, No., 23 Medan, Indonesia
2. Department of Marketing and Logistics Management, College of Management, Chaoyang University of Technology, 413310 No. 168, Jifeng East Road, Wufeng District, Taichung, Taiwan
3. Faculty of Economics and Business, Management Program, University of HKBP Nommensen, Jl. Sutomo, No. 4, Medan, Indonesia
4. Department of Business Administration, College of Management, Chaoyang University of Technology, 413310 No. 168, Jifeng East Road, Wufeng District, Taichung, Taiwan