Handbook of the Birds of India and Pakistan: Together with those of Bangladesh, Nepal, Sikkim, Bhutan and Sri Lanka10 Volume Set

This monumental ten-volume series, the first volume of which was published in 1996, is the most comprehensive and reliable reference work on the birds of the Indian subcontinent. A thoroughly revised second edition with new plates, text revisions, and the addition of new subspecies, it includes information about long-range migration and taxonomic changes, along with life history information, accounts of behavior, ecology, and distribution and migration records.
Anyone with an interest in wildlife on the Indian subcontinent, will find these volumes to be an extraordinary resource.