Sundar, K.S. Gopi (2006). "Flock size, density and habitat selection of four large waterbird species in an agricultural landscape in Uttar Pradesh, India: implications for management". Waterbirds. 29 (3): 365–374. doi:10.1675/1524-4695(2006)29[365:FSDAHS]2.0.CO;2. JSTOR4132592.
Sundar, K.S. Gopi (2006). "Flock size, density and habitat selection of four large waterbird species in an agricultural landscape in Uttar Pradesh, India: implications for management". Waterbirds. 29 (3): 365–374. doi:10.1675/1524-4695(2006)29[365:FSDAHS]2.0.CO;2. JSTOR4132592.