<span class="citations"><p>Gunther Bellmann, "Process for producing a sterile prednisolone gel." U.S. Patent US5811417, issued September 22, 1998.</p>
</span><a href="https://www.google.com/?tbm=pts#q=5811417&amp;tbm=pts" rel="noopener" target="_blank">US5811417</a>