THANKS TO...
Leander Khil for his expert guidance: leanderkhil.com
Kosmos Natural History Books for facilitating my trip: kosmos.de
More information on birding in Vienna:
Birding Austria: bird.at Reference guides:
Collins Bird Guide – Lars Svensson, Killian Mullarney & Dan Zetterström.
Photographic Guide to Birds of Europe, North Africa & the Middle East – Frédéric Jiguet & Aurélien Audevard.