The NY Public Library for the Performing Arts is a gem located in Lincoln Center. Researchers from around the world head to their massive collections of theater, film, dance, music, and recorded sound materials. The public can also use the library. When I was in High School, I went there often to listen to recordings or watch films.
They mount wonderful exhibitions about the arts. Currently they are showing “Border Crossings,” which illustrates dance beyond the mainstream in the first half of 20th century America. The photos, even without reading the explanations, tell a story of creativity that truly makes dance universal.