• Wild Bird Centers of America, Inc.
• Aiken Audubon Society
• Colorado Birding
• Colorado Birding Trail
• Cornell U. Dept. of Ornithology
• Peterson On Line
• Palmer Land Trust
• Colorado Field Ornithologists
• Wild Forever Volunteer Animal Rescue Org.
• E-Nature Science Site
• National Bird Feeding Society
• Ellicott Wildlife Rehabilitation Center