diff --git a/documents/thesis/chapters/beacon_discipline.tex b/documents/thesis/chapters/beacon_discipline.tex
index 15a2a41..18a4f7e 100644
--- a/documents/thesis/chapters/beacon_discipline.tex
+++ b/documents/thesis/chapters/beacon_discipline.tex
@@ -9,9 +9,8 @@
 \begin{document}
 \chapter{Disciplining by Beacon}
 \label{sec:disciplining}
-The main method of synchronising multiple stations is by employing a GNSS.
-This system should deliver timing with an accuracy in the order of $50\ns$.
-
+The time accuracy supplied by a \gls{GNSS} is not enough to do interferometry.
+In this chapter,
 
 
 \section{Beacon}
@@ -98,8 +97,8 @@ This slower timescale allows to count the ticks of the quicker signal.\todo{Exte
 \begin{figure}
 		\includegraphics[width=0.5\textwidth]{beacon/auger/1512.02216.figure2.beacon_beat.png}
 		\caption{
-			From Ref~\cite{PierreAuger:2015aqe}
-			The beacon signal that the \PAObs\ employs.
+			From Ref~\cite{PierreAuger:2015aqe}.
+			The beacon signal that the \acrlong*{PAObs} employs.
 		}
 		\label{fig:beacon:pa}
 \end{figure}
diff --git a/documents/thesis/chapters/introduction.tex b/documents/thesis/chapters/introduction.tex
index 570b521..bc0dda8 100644
--- a/documents/thesis/chapters/introduction.tex
+++ b/documents/thesis/chapters/introduction.tex
@@ -19,18 +19,17 @@
 
 \subsection{Detectors}
 \label{sec:detectors}
-Pierre Auger,
-GRAND
+Standalone devices,
+\gls*{PA},
+\gls*{GRAND}
 
-\subsection{Interferometry}
-\label{sec:interferometry}
-Requires $\sigma_t \lesssim 1\ns$
-
-
-\section{Time Synchronisation}
+\subsubsection{Time Synchronisation}
 \label{sec:timesynchro}
-Need reference system with better accuracy to constrain
-See Section~\ref{sec:grand:gnss}.
+The main method of synchronising multiple stations is by employing a \gls{GNSS}.
+This system should deliver timing with an accuracy in the order of $50\ns$ (see Section~\ref{sec:grand:gnss}).
+\\
+
+Need reference system with better accuracy to constrain (Figure~\ref{fig:reference-clock}).
 
 \begin{figure}
 	\centering
@@ -39,5 +38,17 @@ See Section~\ref{sec:grand:gnss}.
 		Using a reference clock to compare two other clocks.
 	}
 	\label{fig:reference-clock}
+	\todo{
+		redo figure with less margins,
+		remove spines,
+		rotate labels
+	}
 \end{figure}
+
+
+\subsection{Interferometry}
+\label{sec:interferometry}
+Requires $\sigma_t \lesssim 1\ns$
+
+
 \end{document}
diff --git a/documents/thesis/preamble.tex b/documents/thesis/preamble.tex
index 1207c68..0a3d239 100644
--- a/documents/thesis/preamble.tex
+++ b/documents/thesis/preamble.tex
@@ -30,6 +30,8 @@
 
 \usepackage[english]{babel}       % for proper word breaking at line ends
 \usepackage[switch]{lineno}
+\usepackage[acronym]{glossaries}
+\glsdisablehyper
 
 %\usepackage{listings}
 \usepackage{csquotes}
@@ -99,6 +101,8 @@
 
 
 % Names
-\newcommand{\PA}{Pierre~Auger}
-\newcommand{\PAObs}{\PA\ Observatory}
-\newcommand{\GRAND}{Giant Radio Array for Neutrino Detection}
+% Acronyms
+\newacronym{GNSS}{GNSS}{Global Navigation Satellite System}
+\newacronym{GRAND}{GRAND}{Giant Radio Array for Neutrino Detection}
+\newacronym{PA}{PA}{Pierre~Auger}
+\newacronym{PAObs}{PAO}{Pierre~Auger~Observatory}