<i><a href="//commons.wikimedia.org/wiki/Ceanothus_americanus" title="Ceanothus americanus">Ceanothus americanus</a></i>, <a href="//commons.wikimedia.org/w/index.php?title=Sherburne_National_Wildlife_Refuge&amp;action=edit&amp;redlink=1" class="new" title="Sherburne National Wildlife Refuge (page does not exist)">Sherburne National Wildlife Refuge</a>
unknown author, USFWS
United States Fish and Wildlife Service, Sherburne National Wildlife Refuge: <i><a rel="nofollow" class="external text" href="https://web.archive.org/web/20080123082637/http://www.fws.gov/midwest/Sherburne/plantpics/CEAM1.htm">Ceanothus americanus L.</a></i>