Pine Warbler and Red-faced Warbler, From <i>Bird-Lore, Vol. VI, No. 1.</i> Originally issued as Educational Leaflets no. 1-100 of the National Association of Audubon Societies.
<bdi><a href="https://en.wikipedia.org/wiki/en:Robert_Bruce_Horsfall" class="extiw" title="w:en:Robert Bruce Horsfall"><span title="American painter">Robert Bruce Horsfall</span></a>
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