"File:George Boole.jpg." Wikimedia Commons, the free media repository. 19 Nov 2018, 01:17 UTC. 25 Sep 2019, 17:52 <https://commons.wikimedia.org/w/index.php?title=File:George_Boole.jpg&oldid=328260377>.
Source: https://images.app.goo.gl/gZHQUzCUen5ajGgbA
