http://www.smogon.com/forums/threads/sonic-25th-anniversary-sonic-mania-2d-and-sonic-project-2017-3d.3577737/#post-6927915

https://www.youtube.com/watch?v=05OU45K1mbw

http://www.theverge.com/2016/7/23/12262006/sonic-mania-announced-ps4-pc-xbox-one#386273745

https://www.gamnesia.com/news/sonic-mania-is-a-brand-new-2d-sonic-game-that-reimagines-the-classic-sonic#comment-2799595945

http://www.usgamer.net/articles/if-sonics-new-games-are-half-as-good-as-their-marketing-were-in-for-a-treat#comment-7

http://www.gamespot.com/forums/system-wars-314159282/gameplay-video-of-sonic-mania-33359614/?page=1#js-message-354357043

http://veekyforums.com/thread/155325590/video-games/sthg-sonic-the-hedgehog-general.html