Boucot, Arthur J. New Devonian fossils from Saudi Arabia and their biogeographical affinites. Arthur J.Boucot et al. In Senckenbergiana lethaea, 1989, band 69, num.5/6. Frankfurt am Main : s.n., 1989, Senckenbergiana lethaea, 1989, band 69, num.5/6.S.535-596, : .