User talk:189.103.87.77

January 2018
Hello, I'm CASSIOPEIA. I noticed that you made a change to an article, GS formalism, 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.  CASSIOPEIA(talk) 18:05, 24 January 2018 (UTC)