The Presidency  

Guide to the Presidency
Washington, D.C.: CQ Press, 2008.

American President: A Reference Resource
Miller Center at the University of Virginia

Encyclopedia of the American Presidency
New York : Simon & Schuster, 1994
Main Reference JK511.E53 1994 vols. 1 -4

The Presidents: A Reference History
New York : Charles Scribner's Sons : Thomson/Gale, 2002
Main Reference E176.1 .P918 2002

Encyclopedia of Presidential Campaigns, Slogans, Issues, and Platforms
Westport, Conn. : Greenwood Press, 2004
Main Reference E176.1 .R6 2004

Vital Statistics on the Presidency : George Washington to George W. Bush
Washington, D.C.: Congressional Quarterly, 2000
Main Reference JK518 .R34 2009

The American presidents ranked by performance
Jefferson, N.C. : McFarland, c2000
Main Reference     E176.1 .F215 2000 

America at the Polls: A Handbook of American Presidential Election Statistics
Washington, D.C. : Congressional Quarterly, 1994-2001
Main Reference JK524 .A73 1994 vols. 1 - 2

Presidential Elections
Washington, D.C. : Congressional Quarterly, 1995-
Main Reference JK524 .P68 1789/2008

Presidential elections, 1789-2008: county, state, and national mapping of election data
Ann Arbor : University of Michigan Press, c2010.
Main Reference     JK524 .D47 2010       

Historical Atlas of U.S. Presidential Elections 1788-2004
Washington, D.C. : CQ Press, 2006
Main Reference G1201.F9 H5 2006

Encyclopedia of Governance
Thousand Oaks, CA: Sage Reference, 2007

The Encyclopedia of Democracy
Congressional Quarterly, 1995
Main Reference JC423 .E53 1995 vols. 1- 4

Encyclopedia of American Government and Civics
New York, NY : Facts On File, Inc., 2009
Main Reference JK9 .G46 2009 vols. 1 - 3