Figure 1 from US Patent No. 1,510,937: Motor Cycle, granted to <a href="https://en.wikipedia.org/wiki/William_S._Harley" class="extiw" title="w:William S. Harley">William S. Harley</a> and Adam Ziska, Jr. on 1 November 1924
<a href="https://en.wikipedia.org/wiki/William_S._Harley" class="extiw" title="w:William S. Harley">William S. Harley</a>, Adam Ziska Jr.
1919-11-01
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