Bierregaard, R.O., Jr & Kirwan, G.M. (2018). Pearl Kite (Gampsonyx swainsonii). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/52965 on 29 June 2018).