Example:

 <mif:source release="" releaseDate="" xmlns:mif="http://psi.hupo.org/mi/mif300">
    <MIF:names>{0,1}</mif:names>
    <MIF:bibref>{0,1}</mif:bibref>
    <MIF:xref>{0,1}</mif:xref>
    <MIF:attributeList>{0,1}</mif:attributeList>
 </mif:source>