Bourdon, Estelle, Baâdi Bouya, et Mohamed Iarochene. 2005. "Earliest African neornithine bird: A new species of Prophaethontidae (Aves) from the Paleocene of Morocco." Journal of Vertebrate Paleontology 25 (1): 157–70. doi:10.1671/0272-4634(2005)025[0157:EANBAN]2.0.CO;2. Abstractum HTML.
Mayr, Gerald. 2003. "The phylogenetic affinities of the Shoebill (Balaeniceps rex)." Journal für Ornithologie 144 (2): 157–75. Abstractum HTML.