Karl Heinrich Gräffe
Karl Heinrich Gräffe ( 7 November 1799 – 2 December 1873 ) was a German mathematician , who was professor at University of Zurich . 
<triplet> Karl Heinrich Gräffe <subj> 7 November 1799 <obj> date of birth <subj> 2 December 1873 <obj> date of death <subj> mathematician <obj> occupation