diff --git a/docbook-dtds.spec b/docbook-dtds.spec
index 89903cf..c9d8b33 100644
--- a/docbook-dtds.spec
+++ b/docbook-dtds.spec
@@ -1,6 +1,6 @@
 Name:         docbook-dtds
 Version:      20080923
-Release:      3mamba
+Release:      4mamba
 Group:        Applications/Publishing
 Summary:      SGML and XML document type definitions for DocBook.
 License:      Distributable
@@ -95,6 +95,12 @@ function build_docbook() {
    DESTDIR_XML=%{buildroot}%{_datadir}/xml/docbook/schema/dtd
 
    install -d $DESTDIR
+   
+   # remove uninstalled .gml files
+   if [ "$2" = "sgml" ]; then
+      sed -i -e '/ISO 8879/d' -e '/gml/d' docbook.cat
+   fi
+   
    install docbook.cat $DESTDIR/catalog
    install *.dtd $DESTDIR
    install *.mod $DESTDIR
@@ -458,11 +464,14 @@ exit 0
 %dir %{_datadir}/sgml/sgml-iso-entities-8879.1986
 /etc/sgml/sgml-docbook.cat
 /etc/sgml/xml-docbook.cat
-%doc --parents 3.1-sgml/ChangeLog
-%doc --parents 4.1-sgml/ChangeLog
-%doc --parents */*.txt
+#%doc --parents 3.1-sgml/ChangeLog
+#%doc --parents 4.1-sgml/ChangeLog
+#%doc --parents */*.txt
 
 %changelog
+* Thu Dec 03 2020 Silvan Calarco <silvan.calarco@mambasoft.it> 20080923-4mamba
+- remove missing .gml files from installed catalogs
+
 * Thu Jul 18 2019 Silvan Calarco <silvan.calarco@mambasoft.it> 20080923-3mamba
 - create compatibility symlinks to /usr/share/xml/docbook/schema/dtd