mal with size equal to the
number of tees in the group; yellow tees are male, green are female; tees
exposed above the surrounding grass are classified as exposed, others as
unexposed.  We are grateful to Miguel Bernal for making these data
available; they were collected by him as part of a masters project.</p>
    </div>
    <div class="section level2">
    <h2 id="references">References<a class="anchor" aria-label="anchor" href="#references"></a></h2>
    <p>Borchers, D. L., S.T. Buckland, and W. Zucchini