The new Grove dictionary of music and musicians Ref ML 100.M48, is actually a twenty-volume encyclopedia. Crumb Library has a copy. It includes an extensive article on the history of dance. Note the extensive bibliographies under each section. Check Dance in the index for information in other volumes.
Dancing can hurt.
It can also heal. Its healing powers have only recently begun to be systematically explored in our culture. Search Dance therapy in the online catalog. Unfortunately the reference works on dance slight both subjects. General periodicals and newspapers such as Time, Newsweek, Ebony, Atlantic, New Yorker, Rolling Stone, and theater magazines such as Back Stage, Sight and Sound, and Variety also cover the world of dance and dancers.