一般拓扑学基础 张德学 《一般拓扑学基础》 · 第 345 页 · Exercise 11.29 For every pointed space \(X\), the map \(\Sigma_n:\pi_n(X)\to\pi_{n+1}(\Sigma X)\), \([f]\mapsto[\Sigma f]\), is called the suspension homomorphism. 查看原书页面
