Institution: | 1. Department of Mathematics, Minnesota State Community and Technical College, 1900 28th Ave. South, Moorhead, MN 56560, USA;2. Department of Mathematics and Statistics, Wichita State University, Wichita, KS 67260-0033, USA;3. Department of Mathematics, University of Vienna, Vienna, Austria;4. Department of Mathematics and Computer Science, Fort Hays State University, 600 Park Street, Hays, KS 67601, USA |