Proposition 19.5.18F190AF72550B

Proof. Take a quasi-equisingular approximation $(T_ j)_ j$ of $T$ in $\mathcal{Z}_+(X,\alpha )$. Note that $\Delta _{Y_{\bullet }}(T_ j)$ is decreasing in $j$, as follows from 19.5.12. Our assertion follows from (19.5.13) and theorem 16.9.57. $\square$