CHICAGO (CBS) — An Indiana couple whose family has held onto documents from the Civil War for generations is donating the items to the Abraham Lincoln Presidential Library and Museum.

The documents permit a mother and two sisters to visit prisoners of war.

Each item is about the size of a business card and allowed the card owner to visit a relative in Fort Delaware. The camp help more than 30,000 Confederate soldiers during the course of the war, according to the museum.

“Allow Mrs. D.R. Burbank to visit her brother Capt J. N. Taylor, now a prisoner of War at Fort Delaware. June 13, 1864 A. Lincoln,” said the first pass.

Research suggests the note was written for Mary Burbank of Hendersonville, Kentucky. Her brother, James N. Taylor, arrive at Fort Delaware on March 27, 1864.

(Credit: Abraham Lincoln Presidential Library and Museum)

“Allow the bearer, Mrs. Settle, with her daughter to visit her son, at Fort Delaware, Nov. 12, 1864 A. Lincoln,” is what’s written on the second card. It’s not clear who was Mrs. Settle or who was her son.

According to the museum, the passes have been in the possession of the family of Hank and Anna Dowler since the end of the Civil War. An ancestor, Henry Warner, served at Fort Delaware.

“We felt these passes were too important to simply keep them locked up in a safe deposit box,” said Anna Dowler from Greenwood, Indiana. ““We decided they should be given to history, and the Lincoln Presidential Library seemed like the best place.”

The executive director of the Abraham Lincoln Presidential Library and Museum, Alan Lowe, thanked the Dowlers.

“Their generosity ensures everyone can share in this piece of Lincoln’s legacy,” Lowe said. “The passes will be protected for generations to come and eventually will be added to our Papers of Abraham Lincoln project so that anyone in the world can examine them.”

The Papers of Abraham Lincoln is a project dedicated to tracking down documents written by or to Lincoln, then posting copies online along with full transcriptions.

Documents from Lincoln’s first 33 years are available already at