1. Faculty of Petroleum and Natural Gas Engineering, Sahand University of Technology, Tabriz 53318-41133, Iran
2. Department of Petroleum Engineering, College of Engineering and Applied Science, University of Wyoming, 1000 E. University Avenue, Laramie, Wyoming 82071-2000, United States
3. Computer Modelling Group Ltd., 3710 33 Street NW Calgary, Alberta T2L 2M1, Canada