Journal of GeometryApril 2014, Volume 105, Issue 1, pp 185–210 | Cite as11th International Conference on Geometry and ApplicationsVarna (Bulgaria), September 1–6, 2013AuthorsAuthors and affiliationsAlexander KreuzerEmail authorArticleFirst Online: 15 November 2013Received: 23 October 2013 740 Downloads Download to read the full article textCopyright information© Springer Basel 2013Authors and AffiliationsAlexander Kreuzer1Email author1.Universität HamburgHamburgGermany