In the compact Syntax

start =
  element SONG {
    element TITLE        { text },
    (element COMPOSER    { personContent }+
     & element PRODUCER  { personContent }*
     & element PUBLISHER { text }?
     & element LENGTH    { text }?
     & element YEAR      { text }?
     & element ARTIST    { text }+)
  }
personContent =
  element NAME {
    element GIVEN    { text }
    & element FAMILY { text }
  }