A monograph on the anatidae, or duck tribe /.London :Longman, Orme, Brown, Green, & Longman ... and Eddowes, Shrewsbury,1838..biodiversitylibrary.org/page/36002190
Harlekin duck in the brook near Laugarvatn. Author: Christian Bickel 10.06.2004 : This file is licensed under the Creative CommonsAttribution-Share Alike 2.0 Germany license.:. https://creativecommons.org/licenses/by-sa/2.0/de/deed.en CC BY-SA 2.0 de Creative Commons Attribution-Share Alike 2.0 de truetrue.
Summary[edit] Description: Harlequin ducks on the Yellowstone River; Jim Peaco; May 2015; Catalog #20095d; Original #IMG_0782. Date: 13 May 2015, 16:34. Source: Harlequin ducks. Author: Yellowstone National Park from Yellowstone NP, USA.