Fix matrix convex functions citation

1 files changed, 1 insertions, 1 deletions

diff --git a/proofs.tex b/proofs.tex
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--- a/proofs.tex
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@@ -311,7 +311,7 @@ $A-B$ is positive definite (positive semi-definite).  This order allows us to
 define the notion of a \emph{decreasing} as well as  \emph{convex} matrix
 function, similarly to their real counterparts. With this definition, matrix
 inversion is decreasing and convex over symmetric positive definite
-matrices~\cite{convexmatrix}.
+matrices (see Example 3.48 p. 110 in \cite{boyd2004convex}).
 In particular,
 \begin{gather*}
         \forall S\subseteq\mathcal{N},\quad A(S)^{-1} \succeq A(S\cup\{i\})^{-1}