1. Department of Mathematical Sciences, Kent State University, Kent, Ohio, USA 44242.
2. Departments of Computer Science and Mathematical Sciences, Kent State University, Kent, Ohio, USA 44242.
3. Institute for Applied Topology and Topological Structures, Youngstown State University, Youngstown, OH, USA 44555–3609.
4. Institute for Applied Topology and Topological Structures, Youngstown State University, Youngstown, OH, USA 44555–1812.