Neural Entity Linking for Question Answering over Knowledge Graphs / Daniel Vollmers ; 1. Reviewer Prof. Dr. Axel-Cyrille Ngonga Ngomo (Department of Computer Science Paderborn University), 2. Reviewer Prof. Dr. Ricardo Usbeck (Institute of Information Systems Leuphana University Lüneburg) ; Supervisors Prof. Dr. Axel-Cyrille Ngonga Ngomo, Dr. Hamada Mohamed Abdelsamee Zahera