a University of Alabama, Tuscaloosa, AL 35487-0350, USA
b University of Tokyo, Komaba, Meguro-ku, Tokyo 153, Japan
c Calvin College, Grand Rapids, MI 49546, USA
Abstract:
An open subset W of Sn, n 6 or N = 4, and a homotopy equivalence ƒ: S2 × Sn − 4 → W are constructed having the property that ƒ is not homotopic to any topological embedding.