William L. Williamson (1920- ) was Nicholas Murray Butler Librarian at Columbia University from 1954-1964. After 1964 he became Librarian of Montclair, New Jersey State College. In 1966, he was appointed Professor of Library Science at the University of Wisconsin-Madison, and took emeritus status in 1987. He wrote William Frederick Poole and the Modern Library Movement (1963), a biography of that sought to show how Poole's career represented the development of librarianship in the last half of the nineteenth century.

W. F. (William Frederick) Poole (1821-94) was an American librarian, bibliographer, and historian, b. Essex co., Massachusetts. He headed the Boston Athenaeum (1856-1869), the Cincinnati Public Library (1871-1873), Chicago Public Library (1874-1887), and the Newberry Library during its founding years (1887-1894), where he undertook building its collections as well as planning its space. Poole was a founder of the American Library Association (ALA) in 1876 and was active in the organization until his death in 1894. He was President of the American Library Association and the American Historical Association.

He wrote the first general index to U.S. periodicals, Poole's Index to Periodical Literature (1848), a precursor to the Reader's Guide to Periodical Literature, in addition to numerous periodical articles and monographs. His forty-seven years as a librarian can be seen as a portrait of the library profession from its beginning through its transition to the modern era.