You will be given a definition of a task first, then some input of the task.
In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.

Passage: Selling studied mathematics at the Universities of Gottingen and Munich (under Philipp Ludwig von Seidel). He obtained the doctorate in Munich in 1859, under the supervision of Bernhard Riemann. On recommendation of Leopold Kronecker he became professor extraordinarius of mathematics at the University of Wurzburg in 1860 against the will of the philosophical faculty and the mathematics professor Aloys Mayr. There, he also taught astronomy and became conservator-restorer at the astronomical department in 1879. In 1873 he wrote an important paper on binary and ternary quadratic forms which was also translated into French and cited by Henri Poincare, Emile Picard and Paul Gustav Heinrich Bachmann. Beginning with 1877 he also became concerned with insurance, and participated in the reorganization of the pensions in Bavaria on behalf of the Bavarian government. His application for a promotion to professor ordinarius was declined in 1891. In 1906 he became emeritus.
Link Information: Leopold Kronecker (7 December 1823 Answer: 37
Output:
What age was Kronecker when he recommended Selling for a post at the University of Wurzburg?