diff --git a/build/travis_doxygen.sh b/build/travis_doxygen.sh
index 01f8578a..90aea3f6 100644
--- a/build/travis_doxygen.sh
+++ b/build/travis_doxygen.sh
@@ -1,6 +1,7 @@
 #!/bin/sh
 
-if [ "${config}" == "release64" ] && [ "$CC" == "clang" ]; then
+if [ "${config}" = "release64" ] && [ "$CC" = "clang" ]
+then
 	cd /tmp
 	git clone https://github.com/doxygen/doxygen.git
 	cd doxygen