<para>If <literal>MASTER_SITES</literal> is set to 

	<literal>&dollar;{MASTER_SITE_PERL_CPAN}</literal>, 

	then preferred value of <literal>MASTER_SITE_SUBDIR</literal> 

	is top-level hierarchy name instead of author's id. 

	For example, the recommend value for 

	<literal>p5-Module-Name</literal> is <literal>Module</literal>.

	The top-level hierarchy can be examined in 

	<ulink url="http://cpan.org/modules/by-module/">cpan.org</ulink>.

      </para>

      <para>The exception is:</para>

	<itemizedlist>

	  <listitem>

	    <para>The top-level hierarchy name of module does not exist in 

	      <ulink url="http://cpan.org/modules/by-module/">cpan.org</ulink>.

	      In such case, using author's id is more appropriate.

	    </para>

	  </listitem>

	</itemizedlist>

      <note>

	<para>The reasons is that author of the Perl module may

	  change, and it will cause <maketarget>fetch</maketarget>

	  cannot find the required files.</para>

      </note>