by KYW's Karin Phillips

The only known signature made by Abraham Lincoln at Gettysburg, Pa. on the day of his famous address will be put on display later this year at the National Constitution Center.

The rare signature by President Lincoln was acquired at a Sotheby's auction in April by philanthropist Lewis Katz, who has loaned it for ten years to the Constitution Center.  President and CEO Joseph Torsella is delighted:

"This is the only known piece of autograph evidence that ties him to the day. It's (among) four pages from what we think was an autograph book of someone at the time who understood that something big was happening and wanted to get signatures of Lincoln and other officials and dignitaries who were on the stage."

Thursday's announcement comes on the 145th anniversary of the conclusion of the Battle of Gettysburg -- July 3rd, 1863.

Torsella says the signature will be on display in the center's permanent exhibition, "The Story of We the People," probably by November, in time for the anniversary of the Gettysburg address (Nov. 19th, 1863).