002 Tiobe-Index
https://www.tiobe.com/tiobe-index/

002 PYPL-Index
http://pypl.github.io/PYPL.html

002 IEEE-Index
https://spectrum.ieee.org/computing/software/the-2017-top-programming-languages

002 RedMonk-Rankings
http://redmonk.com/sogrady/2017/06/08/language-rankings-6-17/

002 ZDNET
http://www.zdnet.com/article/which-programming-languages-are-most-popular-and-what-does-that-even-mean/