All 13 Russian individuals named in the Mueller indictment were taken from a 2015 article here:

https:// translate.google.com/translate?hl=en&sl=auto&tl=en&u=https%3A%2F%2Fwww.radiosvoboda.org%2Fa%2F26903778.html

Internet Research Agency (IRA), the "Russian troll farm" has been reported by BuzzFeed and other MSM since at least 2013.

ATLANTIC: Russians Online Comment Army (2013)

>https:// www.theatlantic.com/international/archive/2013/10/russias-online-comment-propaganda-army/280432/

>http:// archive.fo/Dl3Xt

>A Russian journalist who visited one such comment-mill, the St. Petersburg Internet Research Agency, met with a coordinator who said the job was not unlike writing copy for a hair dryer: "The only difference is that this hair dryer is a political one."

BUZZFEED: Documents Show How Russia’s Troll Army Hit America (2014)

>https:// archive.fo/2ZomP

>According to the documents, which are attached to several hundred emails sent to the project's leader, Igor Osadchy, the effort was launched in April and is led by a firm called the Internet Research Agency. It's based in a Saint Petersburg suburb, and the documents say it employs hundreds of people across Russia who promote Putin in comments on Russian blogs.