diff --git a/Doxyfile b/Doxyfile
index d5a3a4b7a..03683743b 100644
--- a/Doxyfile
+++ b/Doxyfile
@@ -2614,7 +2614,7 @@ DOT_NUM_THREADS        = 0
 # The default value is: fontname=Helvetica,fontsize=10.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-DOT_COMMON_ATTR        = "fontname=Helvetica,fontsize=10"
+DOT_COMMON_ATTR        = "fontname=Helvetica, fontsize=10"
 
 # DOT_EDGE_ATTR is concatenated with DOT_COMMON_ATTR. For elegant style you can
 # add 'arrowhead=open, arrowtail=open, arrowsize=0.5'. <a
@@ -2623,7 +2623,7 @@ DOT_COMMON_ATTR        = "fontname=Helvetica,fontsize=10"
 # The default value is: labelfontname=Helvetica,labelfontsize=10.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-DOT_EDGE_ATTR          = "labelfontname=Helvetica,labelfontsize=10,arrowhead=open, arrowtail=open, arrowsize=0.5"
+DOT_EDGE_ATTR          = "labelfontname=Helvetica, labelfontsize=10, arrowhead=open, arrowtail=open, arrowsize=0.5"
 
 # DOT_NODE_ATTR is concatenated with DOT_COMMON_ATTR. For view without boxes
 # around nodes set 'shape=plain' or 'shape=plaintext' <a
@@ -2631,7 +2631,7 @@ DOT_EDGE_ATTR          = "labelfontname=Helvetica,labelfontsize=10,arrowhead=ope
 # The default value is: shape=box,height=0.2,width=0.4.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-DOT_NODE_ATTR          = "shape=box,height=0.2,width=0.4"
+DOT_NODE_ATTR          = "shape=box, height=0.2, width=0.4"
 
 # You can set the path where dot can find font specified with fontname in
 # DOT_COMMON_ATTR and others dot attributes.