Attributes / relations provided by
♦ ¹Conservation status and limiting factors in the endangered population of Egyptian vulture (Neophron percnopterus) in the Canary Islands, José A. Donázar, César J. Palacios, Laura Gangoso, Olga Ceballos, María J. González and Fernando Hiraldo, Biological Conservation 107 (2002) 89–97
♦ ²Correlates between morphology, diet and foraging mode in the Ladder Snake Rhinechis scalaris (Schinz, 1822), Juan M. Pleguezuelos , Juan R. Fernández-Cardenete , Santiago Honrubia , Mónica Feriche , Carmen Villafranca, Contributions to Zoology, 76 (3) – 2007