User talk:ArkJohnston

June 2013
Hello, I'm Materialscientist. I noticed that you made a change to an article, but you didn't provide a reliable source. It's been removed for now, but if you'd like to include a citation 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. Thank you. Materialscientist (talk) 01:15, 30 June 2013 (UTC)