Loeb Music Library, Harvard University holds approximately 91,000 books, 143,000 scores, 83,000 sound recordings and video formats, and nearly 1,080 periodical titles.
"The Lester S. Levy Collection of Sheet Music consists of over 29,000 pieces of American popular music. This music was generously donated to The Johns Hopkins University by Lester S. Levy over a period of years starting in 1976 and is now housed in the Special Collections Division of the Milton S. Eisenhower Library. The collection spans the years 1780 to 1980. . . ."
from Georgetown University; "the Labyrinth provides free, organized access to resources in medieval studies. The Labyrinth’s easy-to-use links provide connections to databases, services, texts, and images around the world. Each user will be able to find an Ariadne’s thread through the maze of information on the Web."