Oxford English Dictionary. 
The best information on the meaning of words used by Shakespeare. In addition to the web version, Perkins Library has the printed 2nd edition (1989) in Ref. PE1625 .O87 1989 

LION (Literature Online) 
A fully-searchable collection of over 260,000 works of English and American poetry, drama, and prose, plus biographies, bibliographies and key secondary sources.

The Reference Collection contains other materials helpful in Shakespeare research, including bibliographies of criticism of individual plays ("Hamlet;" "King Lear" in two volumes; "A Midsummer Night's Dream;" and "Richard III.") For a complete list of the Shakespeare material in the Reference Collection, search the Perkins Reference subset of the catalog under the heading "Shakespeare, William" and its subheadings.

The Shakespeare Resources Page was designed by Joline Ezzell and Stephanie Maresch with assistance from professors Joseph Porter and George Williams.