Brieskorn manifold
In mathematics, a Brieskorn manifold or Brieskorn–Phạm manifold,  introduced by , is the intersection of a small sphere around the origin with the singular, complex hypersurface

studied by . Brieskorn manifolds give examples of exotic spheres. References

 This book describes Brieskorn's work relating exotic spheres to singularities of complex manifolds. Singularity theory