Birds of Europe Field Guide
Ecosystema
ЭкоГид: Птицы средней полосы
Birds of Russia Field Guide
Picture Bird - 拍照识鸟
Next Vision Limited
鸟类探测器 - 所有鸟类
Zaheer Udeen
Merlin 鸟种识别 by Cornell Lab
Cornell Lab of Ornithology
European Birds Songs & Calls
Birds of North America: Decoys
Audubon Bird Guide
National Audubon Society
Angry Birds 2
Rovio Entertainment Corporation