VarietyPlus service is also available for coins already encapsulated by NGC.
For coins where the fee column is blank, no VarietyPlus charge is required to
have your coin designated during grading. For coins marked $15, a $15 surcharge
applies to the tier fee during grading, or a $15 fee applies to have the VarietyPlus
designation added to any coin already graded and encapsulated by NGC.
Bugert, Bill. A Register of Liberty Seated Half Dollar Varieties, Volume I, San Francisco Branch Mint. Author, Gettysburg, PA, 2009
Bugert, Bill. A Register of Liberty Seated Half Dollar Varieties, Volume II, Carson City Branch Mint. Author, Gettysburg, PA, 2010
Fivaz, Bill & J.T. Stanton, Ken Potter, Editor. The Cherrypickers' Guide to Rare Die Varieties, 5th Edition, Volume 2. Whitman Publishing, Atlanta, 2012
Wiley, Randy & Bill Bugert. The Complete Guide to Liberty Seated Half Dollars. DLRC Press, Virginia Beach, VA, 1993