User talk:Graeme heald

March 2017
Hello, I'm DVdm. I noticed that you made a change to an article, Four-valued logic, but you didn't provide a source. I’ve removed it for now, but if you’d like to include a citation to a reliable source and re-add it, please do so! If you think I made a mistake, or if you have any questions, you can leave me a message on my talk page. Thanks. DVdm (talk) 15:22, 30 March 2017 (UTC)