| 1. 
  |  | Title: Threatened Birds of the Americas (The Icbp/Iucn Red Data Book ; Pt. 2) by L.P. Gonzaga, N. Krabbe, A. Madrono Nieto, N. J. Collar, T. A. Parker, L. G. Naranjo
 ISBN: 1560982675
 Publisher: Smithsonian Institution Press
 Pub. Date: March, 1993
 List Price: $50.00
 Amazon.com Price: $50.00
 | 
| 2. 
  |  | Title: Threatened Birds of Africa and Related Islands: The Icbp/Iucn Red Data Book, Part 1 by N. J. Collar, S. N. Stuart
 ISBN: 1560982667
 Publisher: Smithsonian Institution Press
 Pub. Date: June, 1993
 List Price: $50.00
 Amazon.com Price: $50.00
 | 
| 3. 
  |  | Title: Threatened birds of the Philippines : the Haribon Foundation/BirdLife International Red data book by N. J. Collar
 ISBN: 9715693342
 Publisher: Bookmark
 Pub. Date: 1999
 
 | 
| 4. 
  |  | Title: Birds to Watch 2: The World List of Threatened Birds (Birdlife Conservation, No 4) by N. J. Collar, M. J. Crosby, International Union for Conservation of Nature and Natural Resources, Birdlife International, A. J. Stattersfield
 ISBN: 1560985283
 Publisher: Smithsonian Institution Press
 Pub. Date: August, 1995
 List Price: $45.00
 Amazon.com Price: $45.00
 | 
| 5. 
  |  | Title: Birds to Watch by N.J. Collar
 ISBN: 0946888302
 Publisher: BirdLife International
 Pub. Date: 1998
 
 | 
| 6. 
  |  | Title: Key Forests for Threatened Birds in Africa by N. J. Collar
 ISBN: 0946888159
 Publisher: International
 Pub. Date: January, 1988
 
 |