D. Zoller, S. Doerfel, R. Jäschke, G. Stumme, and A. Hotho. Journal of Informetrics10 (3):
732--749(June 2016)\copyright 2016 Elsevier. This is an author produced version of a paper subsequently published in Journal of Informetrics . Uploaded in accordance with the publisher's self-archiving policy. Article available under the terms of the CC-BY-NC-ND licence (https://creativecommons.org/licenses/by-nc-nd/4.0/).