diff --git a/m4/ax_gsl.m4 b/m4/ax_gsl.m4
index 314d162d7b658d378a8d0a4f10027dbe2aec3c2a..fe5ae8bdc4ae9edc77a6e4a4781c6f766bf8d276 100644
--- a/m4/ax_gsl.m4
+++ b/m4/ax_gsl.m4
@@ -1,4 +1,4 @@
-dnl Detect the GSL.
+dnl Detect the GSL Library.
 dnl We don't use the official M4 macro since it relies on the script gsl-config,
 dnl which does not work when cross-compiling.
 dnl