Board Thread:Questions?/@comment-24830713-20170812042230

So I'm wondering how everyone knew who composed which music track. I'm asking because is there any source other than official original soundtracks which officially show credit to each composer who composed a certain track? Ex. New Super Mario Bros. DS, Wii or U doesn't officially specify which composers made each music track, same goes for Mario Kart 7, Double Dash, Wii, Wii Fit, etc. Do you just find out by each composer's composition styles? 