1. Physics and Mathematics Department Universidad Iberoamericana 880 Prol. Paseo de la Reforma, Lomas de Santa Fe, Álvaro Obregón Mexico City 01219 Mexico
2. Department of Multidisciplinary Engineering Texas A&M University, Higher Education Center at McAllen 6200 Tres Lagos Blvd. McAllen Texas 78504 USA
3. Department of Mathematics and Physics ITESO, Periférico Sur Manuel Gomez Morin 8585 Tlaquepaque Jalisco 45604 Mexico