Algebraic Topology: Homotopy and Homology
《Algebraic Topology: Homotopy and Homology》 · 第 71 页 · Definition 5.13
A relative CW complex \((X,A)\) has a filtration \(A=X^{-1}\subset X^0\subset X^1\subset\cdots\subset X\) in which each \(X^n\) is obtained from \(X^{n-1}\) by attaching \(n\)-cells and \(X\) has the weak topology for this filtration.