David Allen Sibley

Sibley Field Guide to Birds of Eastern North America - David Sibley

What It's Like to Be a Bird (Adapted for Young Readers): From Flying to Nesting, Eating to Singing--What Birds Are Doing, and Why - David Allen Sibley

The Sibley Guide to Trees - David Allen Sibley

Sibley Field Guide to Birds of Western North America

What It's Like to Be a Bird: From Flying to Nesting, Eating to Singing--What Birds Are Doing, and Why - David Allen Sibley

The Sibley Guide to Birds - David Allen Sibley

Sibley's Birding Basics - David Allen Sibley