1. Department of Mathematics, Western Kentucky University, Bowling Green, Kentucky 42101-3576 USA. ferhan.atici@wku.edu
2. Department of Computer Science, Western Kentucky University, Bowling Green, Kentucky 42101-3576 USA. mustafa.atici@wku.edu
3. Gatton Academy of Science and Mathematics, Bowling Green, Kentucky 42101 USA. michael.belcher403@topper.wku.edu
4. Department of Pathology, Anatomy and Cell Biology, Meharry Medical College, Nashville, Tennessee 37208 USA. dmarshall@mmc.edu