N. Y. Times article about Grandmaster Flash and the legacy of hip-hop
Found the link to this at THE GET DOWN'S Facebook page---it goes into more detail about Grandmaster Flash's background, his use of math to create the art of scratching records to create and properly time breaks and beats, his days of early fame with the Furious Five, and how he feels being an elder statesman of hip-hop (he still DJs full-time year round,too):
http://www.nytimes.com/2016/08/28/nyregion/grandmaster-flash-netflix-series-the-get-down-brings-attention-to-the-hip-hop-pioneer.html?_r=2