benthamopen.com / Rose-ringed Parakeet Psittacula krameri Populations and Numbers in Europe: A Complete Overview. Liviu G. Pârâu, Diederik Strubbe, Emiliano Mori, Mattia Menchetti, Leonardo Ancillotto, André van Kleunen, Rachel L. White, Álvaro Luna, Dailos Hernández-Brito, Marine Le Louarn, Philippe Clergeau, Tamer Albayrak, Detlev Franz, Michael P. Braun, Julia Schroeder, Michael Wink. „The Open Ornithology Journal“, 2016 „9“: „1-13“