DOI: 10.1642/0004-8038(2005)122[http://www.bioone.org/perlserv/?request=get-abstract&doi=10.1642%2F0004-8038%282005%29122%5B0121%3APOTPIS%5D2.0.CO%3B2 HTML abstract*Grimmett, Richard; Inskipp, Carol, Inskipp, Tim & Byers, Clive (1999): "Birds of India, Pakistan, Nepal, Bangladesh, Bhutan, Sri Lanka, and the Maldives".
* Grimmett, Richard; Inskipp, Carol, Inskipp, Tim & Byers, Clive (1999): "Birds of India, Pakistan, Nepal, Bangladesh, Bhutan, Sri Lanka, and the Maldives".