http://pec.lib.wvu.edu/record/P11801940A Birational transformation associated with a national space Cn.Journal article reprint from: <em>Proceedings, West Virginia Academy of Science</em>, v.14 (1940). Also issued as: <em>West Virginia University Bulletin</em>, ser.41:no.4-II (1940:Oct.). Vest, M. L.Transformations (Mathematics)14256