1. Universitas Islam Negeri Walisongo Semarang, Semarang, Jawa Tengah, Indonesia
2. Universitas Gadjah Mada, Yogyakarta, Indonesia
3. Department of English Language, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
4. Universitas Islam Negeri Malik Ibrahim Malang, Jawa Timur, Indonesia