Timeline of A.D.Blumlein patents, by year of filing and by subject area (very broadly), as listed in appendix 2 in <i>R. W. Burns (2000) The Life and Times of A D Blumlein</i>
<a href="//commons.wikimedia.org/w/index.php?title=User:Retired_electrician&amp;action=edit&amp;redlink=1" class="new" title="User:Retired electrician (page does not exist)">Retired electrician</a>
<span class="int-own-work" lang="en">Own work</span> based on data in appendix 2 of <i>R. W. Burns (2000) The Life and Times of A D Blumlein</i>