Google Stops Supporting Noindex in Robots.txt | Radd Interactive
Critical Mistakes in Your Robots.txt Will Break Your Rankings and You Won't Even Know It
seo - Page blocked by robots.txt showing up in site: search results with a description that is a mix of Chinese, English, and German - Webmasters Stack Exchange
How to Hide Content from Search Engines, and Why You May Want To — Legal Marketing & Technology Blog — May 2, 2017
Google Sends Alerts to Sites Using NoIndex in Robots.txt