BLACK-THROATED BLUE WARBLER. <i><a href="//commons.wikimedia.org/wiki/Dendroica_caerulescens" class="mw-redirect" title="Dendroica caerulescens">Dendroica caerulescens</a></i> Female and Male.
Louis Agassiz Fuertes.
2005-05-25
300 ppi scan of the <a href="//commons.wikimedia.org/wiki/National_Geographic_Magazine,_Volume_31" class="mw-redirect" title="National Geographic Magazine, Volume 31">National Geographic Magazine, Volume 31</a> (1917), page 312, panel D.