diff --git a/paper/gtt.tex b/paper/gtt.tex
index a83742b9c9a1e73088cd7395ea17fa0f6251764f..5af4f971d2c6a5c70b60e30e3b2b992003a9ed5c 100644
--- a/paper/gtt.tex
+++ b/paper/gtt.tex
@@ -503,7 +503,7 @@ principle which enables similar reasoning, such as proofs by induction.
 The $\eta$ principles for lazy types \emph{in call-by-name} support dual
 behavioral reasoning about lazy functions, records, and streams.
 
-\textbf{An Axiomatic Approach to Gradual Typing}
+\textbf{An Axiomatic Approach to Gradual Typing.}
 In this paper, we systematically study questions of program equivalence
 for a class of gradually typed languages by working in an
 \emph{axiomatic theory} of gradual program equivalence, a language and