-<!ENTITY url.netbsd "http://www.netbsd.org/">
-<!ENTITY url.openbsd "http://www.openbsd.org/">
-<!ENTITY url.ubuntu "http://www.ubuntu.com/">
-<!ENTITY url.docbook "http://docbook.org/">
-<!ENTITY url.usemarcon "http://www.bl.uk/bibliographic/usemarcon.html">
-<!ENTITY url.libpcap "http://www.tcpdump.org/">
+<!ENTITY url.netbsd "http://www.netbsd.org">
+<!ENTITY url.openbsd "http://www.openbsd.org">
+<!ENTITY url.docbook "http://docbook.org">
+<!ENTITY url.usemarcon "http://www.nationallibrary.fi/libraries/format/usemarcon.html">
+<!ENTITY url.libpcap "http://www.tcpdump.org">