Ballpoint signature, “Agatha Christie,” on an off-white 3 x 1.75 card affixed to a letter from her secretary dated July 14, 1975. In full: “Dame Agatha Christie is now in her 85th year, not in the best of health and regrets that she cannot deal with any further correspondence. Dame Agatha does not like signing photographs of herself but encloses an autographed card with her best wishes.” In fine condition, with tape to the borders. RRAuction COA.