I used this scholarly article for the Unit 1 and 2 essays. It deals w/ hip-hop dance in the beginning and some more recent. It’s not about the underground per se, but has some good points.
http://www.jstor.org.libezproxy2.syr.edu/action/showArticle?doi=10.2307/1477808&Search=yes&term=laboskey&term=sara&item=1&returnArticleService=showArticle&ttl=7&searchUri=%2Faction%2FdoBasicSearch%3FQuery%3DSara%2BLaBoskey%26dc%3DAll%2BDisciplines
Off the link I think Alvaro posted
http://www.undergroundhiphop.com/interviews/
has a few good interviews…the one with One Be Lo was pretty good for this I think.
~~~Dale