I did a simple test where I hire a writer who studies and is practicing medicine to write articles on a niche.
Pretty well written, and it's very insightful. After doing some backlinking I decided to give it a try on Wikipedia. Put up a link at the external link and hope that it stays.
After one day, the link stays.
After two days, the link stays.
It's more than 4 days, the link is still there.
Yes, I know it's a "NO-FOLLOW" tag but I do get traffic from Wikipedia.
So here's another good reason to publish quality content.