diff --git a/text/problem/thething/problem.tex b/text/problem/thething/problem.tex
index 90b22a2..db43148 100644
--- a/text/problem/thething/problem.tex
+++ b/text/problem/thething/problem.tex
@@ -80,7 +80,7 @@ Theorem~\ref{theor:thething-prv} states how to achieve the desired privacy goal
 \begin{theorem}
   [{\Thething} privacy]
   \label{theor:thething-prv}
-  Let $\mathcal{M}$ be a mechanism with input a time series $S_T$, where $T$ is the set of the  involved timestamps, and $L \subseteq T$ be the set of {\thething}  timestamps.
+  Let $\mathcal{M}$ be a mechanism with input a time series $S_T$, where $T$ is the set of the  involved timestamps, and $L \subseteq T$ be the set of {\thething} timestamps.
   $\mathcal{M}$ is decomposed to $\varepsilon$-differential private sub-mechanisms $\mathcal{M}_t$, for every $t \in T$, which apply independent randomness to the event at $t$.
   Then, given a privacy budget $\varepsilon$, $\mathcal{M}$ satisfies {\thething} privacy if for any $t$ it holds that
   $$ \sum_{i\in L \cup \{t\}} \varepsilon_i \leq \varepsilon$$