lie-algebras-and-their-representations

diff --git a/sections/introduction.tex b/sections/introduction.tex
@@ -679,10 +679,10 @@ algebraic affair, but the universal enveloping algebra of the Lie algebra of a
 Lie group \(G\) is in fact intimately related with the algebra
 \(\operatorname{Diff}(G)\) of differential operators \(C^\infty(G) \to
 C^\infty(G)\) -- i.e. \(\mathbb{R}\)-linear endomorphisms \(C^\infty(G) \to
-C^\infty(G)\) of finite order, as defined in Coutinho's \citetitle{coutinho}
-\cite[ch.~3]{coutinho} for example. Algebras of differential operators and
-their modules are the subject of the theory of \(D\)-modules, which has seen
-remarkable progress in the past century. Specifically, we find\dots
+C^\infty(G)\) of finite order, as defined in \cite[ch.~3]{coutinho} for
+example. Algebras of differential operators and their modules are the subject
+of the theory of \(D\)-modules, which has seen remarkable progress in the past
+century. Specifically, we find\dots
 
 \begin{proposition}\label{thm:geometric-realization-of-uni-env}
   Let \(G\) be a Lie group and \(\mathfrak{g}\) be its Lie algebra. Denote by