Rook, Bird Identification Guide
Por um escritor misterioso
Descrição
Identify a Rook, Corvus frugilegus
Rook, crow or raven? How to tell them apart - Woodland Trust
Europe's Birds: An Identification Guide – Association of Field Ornithologists
Corvids: Their Differences and Similarities – Spiritual Carol Blog
Rook, Bird Identification Guide
Rook (Corvus frugilegus) Dimensions & Drawings
Rook Bird Facts (Corvus frugilegus)
American Crow - Montana Field Guide
Rook - Crossley Bird ID Guides
British crow family guide: identification, habitat and species facts
File:Tamaulipas Crow From The Crossley ID Guide Eastern Birds.jpg - Wikimedia Commons
ID Guide to British crows [Corvids] – British Naturalists' Association
Differences Between an American Crow and a Common Raven (with Map, Pictures, and Sounds) - Avian Report
