<span class="citations"><p>Vincenzo Cannata, Giancarlo Tamerlani, Mauro Morotti, "Process for the synthesis of the levodopa." U.S. Patent US4962223, issued December, 1986.</p>
</span><a href="https://www.google.com/?tbm=pts#q=4962223&amp;tbm=pts" rel="noopener" target="_blank">US4962223</a>