Algebraic Topology
《Algebraic Topology》 · 第 381 页 · Section 4.2
For based maps \(f:S^k\to X\) and \(g:S^\ell\to X\), the Whitehead product \([f,g]:S^{k+\ell-1}\to X\) is obtained by composing the attaching map of the top cell of \(S^k\times S^\ell\) with \(f\vee g\).