diff --git a/docs/reference/shell/Makefile.am b/docs/reference/shell/Makefile.am
index 80a322982..b9f1ba475 100644
--- a/docs/reference/shell/Makefile.am
+++ b/docs/reference/shell/Makefile.am
@@ -18,11 +18,10 @@ DOC_MODULE=shell
 # The top-level SGML file. You can change this if you want to.
 DOC_MAIN_SGML_FILE=$(DOC_MODULE)-docs.sgml
 
-# Directories containing the source code, relative to $(srcdir).
+# Directories containing the source code
 # gtk-doc will search all .c and .h files beneath these paths
 # for inline comments documenting functions and macros.
-# e.g. DOC_SOURCE_DIR=../../../gtk ../../../gdk
-DOC_SOURCE_DIR=../../../src
+DOC_SOURCE_DIR=$(top_srcdir)/src
 
 # Extra options to pass to gtkdoc-scangobj. Not normally needed.
 SCANGOBJ_OPTIONS=
diff --git a/docs/reference/st/Makefile.am b/docs/reference/st/Makefile.am
index 51473a39a..9a5efd045 100644
--- a/docs/reference/st/Makefile.am
+++ b/docs/reference/st/Makefile.am
@@ -18,11 +18,10 @@ DOC_MODULE=st
 # The top-level SGML file. You can change this if you want to.
 DOC_MAIN_SGML_FILE=$(DOC_MODULE)-docs.sgml
 
-# Directories containing the source code, relative to $(srcdir).
+# Directories containing the source code
 # gtk-doc will search all .c and .h files beneath these paths
 # for inline comments documenting functions and macros.
-# e.g. DOC_SOURCE_DIR=../../../gtk ../../../gdk
-DOC_SOURCE_DIR=../../../src/st
+DOC_SOURCE_DIR=$(top_srcdir)/src/st
 
 # Extra options to pass to gtkdoc-scangobj. Not normally needed.
 SCANGOBJ_OPTIONS=