Yourke's current switch logic c. 1955. After Rymaszewski et al. (1981). "Semiconductor Logic Technology in IBM." IBM J. Res. Develop. 25, 608.
<a href="//commons.wikimedia.org/wiki/User:Gerry_Ashton" title="User:Gerry Ashton">Gerry Ashton</a>
<span class="int-own-work" lang="en">Own work</span>