// <!ELEMENT avp (single | grouped)>
// <!ATTLIST avp name CDATA #REQUIREDcode CDATA #REQUIRED vendor-name CDATA #IMPLIED may-encrypt (yes | no) #IMPLIED v-bit (must | may | shouldnot | mustnot) #IMPLIED m-bit (must | may | shouldnot | mustnot) #IMPLIED p-bit (must | may | shouldnot | mustnot) #IMPLIED>
// <!ELEMENT single (label*)>
// <!ELEMENT avp (single | grouped)>
// <!ATTLIST avp name CDATA #REQUIREDcode CDATA #REQUIRED vendor-name CDATA #IMPLIED may-encrypt (yes | no) #IMPLIED v-bit (must | may | shouldnot | mustnot) #IMPLIED m-bit (must | may | shouldnot | mustnot) #IMPLIED p-bit (must | may | shouldnot | mustnot) #IMPLIED>
// <!ELEMENT single (label*)>