Question:
Which employer did Paul Stäckel work for in Aug, 1917?

Context:
 Paul Stäckel works for University of Königsberg from Jan, 1896 to Jan, 1897. 
 Paul Stäckel works for University of Halle-Wittenberg from Jan, 1891 to Jan, 1895. 
 Paul Stäckel works for University of Kiel from Jan, 1897 to Jan, 1905. 
 Paul Stäckel works for Leibniz University Hannover from Jan, 1905 to Jan, 1908. 
 Paul Stäckel works for Heidelberg University from Jan, 1912 to Jan, 1919. 
 Paul Stäckel works for Karlsruhe Institute of Technology from Jan, 1908 to Jan, 1912.

Answer:
Heidelberg University