Suppose that maps between three spheres forms a fibration. Show that \(k=n-1\).
Diagram description: \(S^k\) maps to \(S^{n+k}\) by \(\iota \), and \(S^{n+k}\) maps down to \(S^n\) by \(p\).
By giving examples, show that such a fibration is indeed possible for some \(n\).