Collins - A Guide to Identification and Behaviour.

Every species illustrated.  Comprehensive.  Highly illustrated.

Institute of Terrestrial Ecology Natural Environment Research Council  

A Collins Field Guide Book to the Birds of West Africa.

Collins illustrated checklist of Birds of Western & Central Africa.

Breeds of Poultry & Their Characteristics - by Dr. Joseph Batty.

For Those Who Care

Full of helpful advice on how to choose and look after a budgerigar.