↑ "HTML meta tag". www.w3schools.com. Retrieved 2021-04-22. ↑ "Meta tags that Google understands - Search Console Help". support.google.com. Retrieved 2018-10-15. ↑ Statistic (June 4, 1997), META attributes by count, Vancouver Webpages, retrieved June 3, 2007 ↑ "In 2007, 37 leaders in search engine optimisation concluded that having keywords in the keywords attribute is little to none."