The Development of Harvard University since the inauguration of President Eliot, 1869-1929
Edited by Samuel Eliot Morison (1930)
See Chapter 30, "The Law School 1817-1929"
The Law at Harvard : A History of Ideas and Men, 1817-1967
By Arthur E. Sutherland (1967)
The High Citadel: The Influence of Harvard Law School
By Joel Seligman, with the assistance of Lynne Bernabei; Introduction by Ralph Nader (1978)
Logic and Experience: The Origin of Modern American Legal Education, 1800-1920
By William P. LaPiana (1994)
On the Battlefield of Merit: Harvard Law School, the first century
By Daniel R. Coquillette, Bruce A. Kimball (2015)
History of the Harvard Law School and of Early Legal Conditions in America
By Charles Warren, 1908.
Full text of volumes 1-3 is available through Google Books and The Making of Modern Law.
The Centennial History of the Harvard Law School, 1817-1917
Full text is available through Google Books.