illustration of <i><a href="//commons.wikimedia.org/wiki/Amerorchis_rotundifolia" class="mw-redirect" title="Amerorchis rotundifolia">Amerorchis rotundifolia</a></i> in Britton, N.L., and A. Brown: <i>An illustrated flora of the northern United States, Canada and the British Possessions</i>. Vol. 1: 551.
Britton, N.L., and A. Brown
upload 07-19-2008, published 1913
<a rel="nofollow" class="external free" href="https://plants.usda.gov/gallery/pubs/orro3_001_pvd.tif">http://plants.usda.gov/gallery/pubs/orro3_001_pvd.tif</a>