File_MARC

<?php

require 'File/MARCXML.php' ;

$authority = '<?xml version="1.0" encoding="UTF-8"?>
<collection xmlns="http://www.loc.gov/MARC21/slim">
 <record>
  <leader>00143     2200073   4500 </leader>
  <controlfield tag="001">260</controlfield>
  <datafield tag="100" ind1=" " ind2=" ">
   <subfield code="a">20120402afrey50      ba0</subfield>
  </datafield>
  <datafield tag="152" ind1=" " ind2=" ">
   <subfield code="b">PERSO_NAME</subfield>
  </datafield>
  <datafield tag="200" ind1=" " ind2=" ">
   <subfield code="a">Severin</subfield>
   <subfield code="b">Georgii</subfield>
  </datafield>
 </record>
</collection>' ;

$authorities = new File_MARCXML ( $authority, File_MARC::SOURCE_STRING ) ;

$record = $authorities -> next ( ) ;

$leader = $record -> getLeader ( ) ;

$newleader = rtrim ( $leader ) ;

$record -> setLeader ( $newleader ) ;

echo $record -> toXML ( ) ;

?>