User talk:42.201.171.73

Recent edit to A History of Pi
Hello, and welcome to Wikipedia. I noticed that you made a change to an article, A History of Pi, 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 need guidance on referencing, please see the referencing for beginners tutorial, or if you think I made a mistake, you can leave me a message on my talk page. Thank you!  — Ruyter (talk • edits)  17:21, 2 January 2019 (UTC)