1. Fakulti Teknologi Kejuruteraan Mekanikal dan Pembuatan, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, Melaka, Malaysia
2. Faculty of Science, Department of Mathematics, Universiti Putra Malaysia, Selangor, Malaysia
3. Institute for Mathematical Research, Universiti Putra Malaysia, Selangor, Malaysia
4. Department of Mathematics, Babeş-Bolyai University, Cluj-Napoca, Romania