il and Malcolm Wallace, 2002-2005.
<p>
<em>hat-observe</em> is
&copy; copyright to Malcolm Wallace and Thorsten Brehm, 2001-2004.
<p>
<em>hat-detect</em> is
&copy; copyright to Malcolm Wallace and Thorsten Brehm, 2001-2004.
<p>
<em>hat-trail</em> is
&copy; copyright to Malcolm Wallace, 2002-2004.
<p>
<em>hat-stack</em> is
&copy; copyright to Malcolm Wallace, 2001-2004.
<p>
<em>hat-check</em> is
&copy; copyright to Colin Runciman, 2001-2004.
<p>
<em>hat-cover</em> is
&copy; copyright to Colin Runciman, 2004.