Reference

Göran Nilson, Claes Andrén (1988): Vipera lebetina transmediterranea, a new subspecies of viper from North Africa, with remarks on the taxonomy of Vipera lebetina and Vipera mauritanica (Reptilia: Viperidae) – Bonn zoological Bulletin - früher Bonner Zoologische Beiträge. – 39: 371 - 379.