Apt Ulrich or Abt, the Elder. Late 15th- to early 16th-c. German painter. His works include the Matthiius Altarpiece and the dramatic and experimental Lamentation over the Dead (Christ, both in Munich. The Portrait of a Young Man, discovered in the 19th c, was remarkably like A.'s work but showed the initials 'L.S.' on a piece of armour. A.'s best works were reattributed to 'L.S.' until it was recently shown that the initials were simply those of the armourer.