Removed parts from Zhu citations.

src/op/c-star/unitary.tex

@@ -42,7 +42,7 @@
 \label{proposition:unitary-spectrum}
     Let $A$ be a unital $C^*$-algebra and $x \in A$ be unitary, then $\sigma_A(x) \subset \partial B_\complex(0, 1)$. 
 \end{proposition}
-\begin{proof}[Proof, {{\cite[Proposition II.8.2]{Zhu}}}. ]
+\begin{proof}[Proof, {{\cite[Proposition 8.2]{Zhu}}}. ]
     By \autoref{lemma:unitary-unit}, $\norm{x}_A = 1$, so $\sigma_A(x) \subset \ol{B_\complex(0, 1)}$. Thus
     \[
     \bracsn{\ol{\lambda}|\lambda \in \sigma_A(x)} = \sigma_A(x^*) = \sigma_A(x^{-1}) \subset \ol{\complex \setminus B_\complex(0, 1)}