Mineski.net - Goodbye 2k MMR, hello Herald! Dota 2's new Seasonal Rank is finally here. For more info : blog.dota2.com/2017/11/seasonal-ranked-update | Facebook
Dota 2 Ranks: MMR, Medals and Ranking
Matchmaking/Seasonal Rankings - Dota 2 Wiki
Dota 2's new 'medal' ranked MMR system released for all players - The Flying Courier