Fix error in lcov target
diff --git a/Makefile b/Makefile
index 6eeb978..17544a5 100644
--- a/Makefile
+++ b/Makefile
@@ -71,7 +71,7 @@
 	lcov --add-tracefile files.info --add-tracefile tests.info -o all.info
 	lcov --remove all.info -o final.info '*.h'
 	gendesc tests/Descriptions.txt -o descriptions
-	genhtml --title mbed TLS --description-file descriptions --keep-descriptions --legend --no-branch-coverage -o Coverage final.info
+	genhtml --title "mbed TLS" --description-file descriptions --keep-descriptions --legend --no-branch-coverage -o Coverage final.info
 	rm -f files.info tests.info all.info final.info descriptions
 
 apidoc: