paragraph: Wanderjahre and marriage (1490-94) After completing his term of apprenticeship, Durer followed the common German custom of taking Wanderjahre--in effect gap years --in which the apprentice learned skills from artists in other areas; Durer was to spend about four years away. He left in 1490, possibly to work under Martin Schongauer, the leading engraver of Northern Europe, but who died shortly before Durer's arrival at Colmar in 1492. It is unclear where Durer travelled in the intervening period, though it is likely that he went to Frankfurt and the Netherlands. In Colmar, Durer was welcomed by Schongauer's brothers, the goldsmiths Caspar and Paul and the painter Ludwig. In 1493 Durer went to Strasbourg, where he would have experienced the sculpture of Nikolaus Gerhaert. Durer's first painted self-portrait (now in the Louvre) was painted at this time, probably to be sent back to his fiancee in Nuremberg. In early 1492 Durer travelled to Basel to stay with another brother of Martin Schongauer, the goldsmith Georg. Very soon after his return to Nuremberg, on 7 July 1494, at the age of 23, Durer was married to Agnes Frey following an arrangement made during his absence. Agnes was the daughter of a prominent brass worker (and amateur harpist) in the city. However, no children resulted from the marriage. 
question: Who was Durer's father in law?
answer: Georg Schongauer