周厚坤打字机的照片和描述，出自《新青年》
<bdi><a href="https://en.wikipedia.org/wiki/en:Hu_Shih" class="extiw" title="w:en:Hu Shih"><span title="Chinese philosopher, essayist and diplomate">Hu Shih</span></a>
</bdi>
<p><cite class="book" style="font-style:normal">Mullaney, Thomas S. (2017)      <i> The Chinese Typewriter: A History</i>, p. 144  <small><a href="https://en.wikipedia.org/wiki/International_Standard_Book_Number" class="extiw" title="en:International Standard Book Number">ISBN</a>:  <a href="//commons.wikimedia.org/wiki/Special:BookSources/9780262036368" title="Special:BookSources/9780262036368">9780262036368</a>. </small></cite>
</p>
藏晖室劄记，新青年卷三，第二号