@XDATA{macmillan:pub,
  IDS       = {macmillan:pubALIAS},
  PUBLISHER = {Macmillan}
}

@XDATA{macmillan:loc,
  LOCATION = {New York and London},
  NOTE     = {A Note} 
}

@XDATA{macmillan,
  IDS   = {macmillanalias},
  XDATA = {macmillan:pubALIAS, macmillan:loc}
}


@BOOK{xd1,
  AUTHOR        = {Edward Ellington},
  DATE          = {2007},
  XDATA         = {macmillanalias, missingxd}
}

@BOOK{xd2,
  AUTHOR        = {Peter Pillington},
  DATE          = {2003},
  PUBLISHER     = {Routledge},
  XDATA         = {macmillan:loc, bltxxd1}
}

% Loop detection test
@XDATA{loop:1,
  NOTE = {Note}
}

@XDATA{loop:2,
  XDATA = {loop:3}
}

@XDATA{loop:3,
  XDATA = {loop}
}

@XDATA{loop,
  XDATA = {loop:1, loop:2}
}

@BOOK{xd3,
  AUTHOR        = {Edward Ellington},
  DATE          = {1923},
  XDATA         = {loop}
}
