Twin directories of docbook-tools:

[DIR]  ftp://bo.mirror.garr.it/pub/1/sourceware.org/docbook-tools/
[DIR]  ftp://ftp.funet.fi/.m/mirrors2/sources.redhat.com/pub/docbook-tools/
[DIR]  ftp://sunsite.mff.cuni.cz/MIRRORS/sources.redhat.com/pub/docbook-tools/
[DIR]  ftp://ftp.esat.net/mirrors/.2/sources.redhat.com/pub/docbook-tools/
[DIR]  ftp://gcc.gnu.org/pub/docbook-tools/
[DIR]  ftp://ftp.li.kernel.org/pub/.3/sources.redhat.com/docbook-tools/
[DIR]  ftp://128.118.2.96/pub/.mirrors/2/cygwin.com/docbook-tools/
[DIR]  ftp://ftp2.au.freebsd.org/pub/sourceware/docbook-tools/
[DIR]  ftp://ftp.cs.nott.ac.uk/sites/sources.redhat.com/ftp/docbook-tools/
[DIR]  ftp://ftp.sai.msu.su/pub/unix/WWW/tools/converters/docbook-tools/