<!ENTITY url.ubuntu "http://www.ubuntu.com/">
<!ENTITY url.docbook "http://docbook.org/">
<!ENTITY url.usemarcon "http://www.bl.uk/services/bibliographic/usemarcon.html">
<!ENTITY url.ubuntu "http://www.ubuntu.com/">
<!ENTITY url.docbook "http://docbook.org/">
<!ENTITY url.usemarcon "http://www.bl.uk/services/bibliographic/usemarcon.html">