diff --git a/Paper.tex b/Paper.tex
index 1948eb98..87ba3880 100644
--- a/Paper.tex
+++ b/Paper.tex
@@ -774,7 +774,11 @@ \section{Message Call} \label{ch:call}
 \boldsymbol{\sigma} & \text{if} \quad \boldsymbol{\sigma}^{**} = \varnothing \\
 \boldsymbol{\sigma}^{**} & \text{otherwise}
 \end{cases} \\
-(\boldsymbol{\sigma}^{**}, g', \mathbf{s}, \mathbf{o}) & \equiv & \begin{cases}
+g' & \equiv & \begin{cases}
+0 & \text{if} \quad \boldsymbol{\sigma}^{**} = \varnothing \\
+g^{**} & \text{otherwise}
+\end{cases} \\
+(\boldsymbol{\sigma}^{**}, g^{**}, \mathbf{s}, \mathbf{o}) & \equiv & \begin{cases}
 \Xi_{\mathtt{ECREC}}(\boldsymbol{\sigma}_1, g, I) & \text{if} \quad r = 1 \\
 \Xi_{\mathtt{SHA256}}(\boldsymbol{\sigma}_1, g, I) & \text{if} \quad r = 2 \\
 \Xi_{\mathtt{RIP160}}(\boldsymbol{\sigma}_1, g, I) & \text{if} \quad r = 3 \\