de Kloet, RS; de Kloet SR (2005). "The evolution with the spindlin gene in birds: Sequence Evaluation of an intron from the spindlin W and Z gene reveals four main divisions in the Psittaciformes". Ranges are based https://safattmb213725.bleepblogs.com/30908391/cockatoos-parrots-for-sale-an-overview