<a href="https://en.wikipedia.org/wiki/Calvert_Vaux" class="extiw" title="en:Calvert Vaux">Calvert Vaux</a>
Unknown author<span style="display: none;">Unknown author</span>
Graf, John, <i>Chicago's Parks</i> Arcadia Publishing, 2000, p. 94., <a href="//commons.wikimedia.org/wiki/Special:BookSources/0-7385-0716-4" title="Special:BookSources/0-7385-0716-4">ISBN 0-7385-0716-4</a>.