1. English Education Department, Universitas Muhammadiyah Prof. DR. HAMKA, Jakarta, Indonesia
2. Directorate of Instructor and Training Personnel, Ministry of Labour, Career Guidance for Government Training Instructors, Jakarta, Indonesia
3. College of Education, Central Luzon State University, Science City of Muñoz, Nueva Ecija, Philippines
4. English Education Department, Universitas Jambi, Jambi, Indonesia