He wrote the two - volume book and co-authored The Kouprey : An Action Plan for Its Conservation ISBN 2 - 88032 - 972 - 8 .
The two - volume book is the Birds of Vietnam .
He wrote the two - volume book , The Birds of Vietnam , and co-authored The Kouprey : An Action Plan for Its Conservation ISBN 2 - 88032 - 972 - 8 .