docbook-xsl

$ locale && cat index.xml && xsltproc --catalogs --xinclude --nonet --output index.html lib/docbook-xsl-1.76.1/html/docbook.xsl index.xml && cat index.html
LANG=en_AU.utf-8
LC_CTYPE="en_AU.utf-8"
LC_NUMERIC="en_AU.utf-8"
LC_TIME="en_AU.utf-8"
LC_COLLATE="en_AU.utf-8"
LC_MONETARY="en_AU.utf-8"
LC_MESSAGES="en_AU.utf-8"
LC_PAPER="en_AU.utf-8"
LC_NAME="en_AU.utf-8"
LC_ADDRESS="en_AU.utf-8"
LC_TELEPHONE="en_AU.utf-8"
LC_MEASUREMENT="en_AU.utf-8"
LC_IDENTIFICATION="en_AU.utf-8"
LC_ALL=
<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
    "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">

<book>
  <bookinfo>
    <title>Hello</title>
  </bookinfo>
  <part id="Part1">
    <title>Swizzle</title>
    <chapter>
      <title>Swazzle</title>
      <sect1>
        <title>Swuzzle</title>
        <para>zing</para>
      </sect1>
    </chapter>
  </part>
</book>

Variable $SGML_CATALOG_FILES not set
<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Hello</title><meta name="generator" content="DocBook XSL Stylesheets V1.76.1"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="book" title="Hello"><div class="titlepage"><div><div><h1 class="title"><a name="id541812"></a>Hello</h1></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="part"><a href="#Part1">I. Swizzle</a></span></dt><dd><dl><dt><span class="chapter"><a href="#id531659">1. Swazzle</a></span></dt><dd><dl><dt><span class="sect1"><a href="#id539534">Swuzzle</a></span></dt></dl></dd></dl></dd></dl></div><div class="part" title="Part�I.�Swizzle"><div class="titlepage"><div><div><h1 class="title"><a name="Part1"></a>Part�I.�Swizzle</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="chapter"><a href="#id531659">1. Swazzle</a></span></dt><dd><dl><dt><span class="sect1"><a href="#id539534">Swuzzle</a></span></dt></dl></dd></dl></div><div class="chapter" title="Chapter�1.�Swazzle"><div class="titlepage"><div><div><h2 class="title"><a name="id531659"></a>Chapter�1.�Swazzle</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="sect1"><a href="#id539534">Swuzzle</a></span></dt></dl></div><div class="sect1" title="Swuzzle"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id539534"></a>Swuzzle</h2></div></div></div><p>zing</p></div></div></div></div></body></html>