Library card

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Library card
The First Doctor's library card held by the Eleventh Doctor (TV: The Vampires of Venice)

A library card was a form of identification used to borrow books from libraries. The First Doctor received a library card from Shoreditch Library having registered there sometime between his arrival in May 1963 and November 1963, when the card was due to expire. The Doctor kept the library card as he departed Shoreditch on 22 November and retained it to as late as his eleventh incarnation, who mistakenly presented it as his identification to a group of Saturnyns. Having never renewed it, the card still sported the image of his first incarnation. (TV: The Vampires of Venice)

The Thirteenth Doctor still had her first incarnation's library card as well as cards for her ninth, tenth, eleventh, and twelfth incarnations. (COMIC: A Little Help from My Friends)

Ianto Jones used a library card for identification when infiltrating Blind Summit for Torchwood One as a prospective test subject. He claimed this was all he had, as he did not drive. (AUDIO: Blind Summit)