diff --git a/doc/Doxyfile b/doc/Doxyfile
index 0f80df9c..c9e6933a 100644
--- a/doc/Doxyfile
+++ b/doc/Doxyfile
@@ -134,7 +134,12 @@ HTML_HEADER =
 HTML_FOOTER = ../doc/doxygen/footer.html
 HTML_EXTRA_STYLESHEET = ../doc/doxygen/custom.css
 HTML_ALIGN_MEMBERS = YES
-HTML_EXTRA_FILES = ../doc/fluidsettings.xml ../doc/fluidsettings.xsl ../doc/FluidMixer.pdf ../doc/FluidMixer.jpg
+HTML_EXTRA_FILES = \
+../doc/fluidsettings.xml \
+../doc/fluidsettings.xsl \
+../doc/FluidMixer.pdf \
+../doc/FluidMixer.jpg
+
 GENERATE_HTMLHELP = NO
 GENERATE_DOCSET = NO
 DOCSET_FEEDNAME = "Doxygen generated docs"
diff --git a/doc/Doxyfile.cmake b/doc/Doxyfile.cmake
index 305ca9db..1e8f63e6 100644
--- a/doc/Doxyfile.cmake
+++ b/doc/Doxyfile.cmake
@@ -136,7 +136,12 @@ HTML_HEADER =
 HTML_FOOTER = @CMAKE_SOURCE_DIR@/doc/doxygen/footer.html
 HTML_EXTRA_STYLESHEET = @CMAKE_SOURCE_DIR@/doc/doxygen/custom.css
 HTML_ALIGN_MEMBERS = YES
-HTML_EXTRA_FILES = @CMAKE_SOURCE_DIR@/doc/fluidsettings.xml @CMAKE_SOURCE_DIR@/doc/fluidsettings.xsl @CMAKE_SOURCE_DIR@/doc/FluidMixer.pdf @CMAKE_SOURCE_DIR@/doc/FluidMixer.jpg
+HTML_EXTRA_FILES = \
+@CMAKE_SOURCE_DIR@/doc/fluidsettings.xml \
+@CMAKE_SOURCE_DIR@/doc/fluidsettings.xsl \
+@CMAKE_SOURCE_DIR@/doc/FluidMixer.pdf \
+@CMAKE_SOURCE_DIR@/doc/FluidMixer.jpg
+
 GENERATE_HTMLHELP = NO
 GENERATE_DOCSET = NO
 DOCSET_FEEDNAME = "Doxygen generated docs"