[1NW] Let \(I,Jβ {\mathbb {R}}\) be intervals. Let \(πΎ:Iβ X\) and \(πΏ:Jβ X\) be two curves. We will write \(πΎβΌπΏ\) if there exists an increasing homeomorphism 1 \(π:Iβ J\) such that \(πΎ=πΏβ¦π\).