Affiliation: | (1) Department of Mathematics, Drexel University, 19104 Philadelphia, PA, USA;(2) Department of Mathematics and Computer, Science Truman State University, 63501 Kirksville, MO, USA;(3) Department of Physics, Drexel University, 19104 Philadelphia, PA, USA;(4) Department of Computer Science, University of South Florida, 4202 Fowler Avenue, 33620 Tampa, FL;(5) Department of Mathematics, DePaul University, 60614 Chicago, IL |