I'm using 2 xhtml files for my docx file.
One is the body of the docx and the other one is udes by the header.
1st file is named c.xhtml and 2nd one is named cc.xhtml.
In order to test my file, I use a simple xhtml :
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta name="generator" content="HTML Tidy for Java (vers. 2009-12-01), see jtidy.sourceforge.net" />
<title></title>
</head>
<body>
<p>Hello ...