Remark 81.22.2. Let $S$, $B$, $X$, $\mathcal{L}$, $s$, $i : D \to X$ be as in Definition 81.22.1 and assume that $\mathcal{L}|_ D \cong \mathcal{O}_ D$. In this case we can define a canonical map $i^* : Z_{k + 1}(X) \to Z_ k(D)$ on cycles, by requiring that $i^*[W] = 0$ whenever $W \subset D$. The possibility to do this will be useful later on.

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