Wiesenschafstelze

Motacilla flava flava, Blue-headed Wagtail

del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.) (2014). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/ on 30 October 2018).
Karte: San Jose, 1 April 2007, adapted by Chumwa, 6 May 2008 [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/)], via Wikimedia Commons
Glutz von Blotzheim, U (1988) Handbuch der Vögel Mitteleuropas. Band 13/1. Bearb. von Urs N. Glutz von Blotzheim; Kurt M. Bauer. – Wiesbaden: Aula-Verl.
Alström P, Mild K (2010): Pipits & Wagtails of Europe and North America. Christophe Helm, London. Bloomsbury Publishing. Kindle-Version.