@misc{gdea_3705,
          editor = {Patrick Healy and Nikola S. Nikolov},
           title = {Complexity Results for Three-dimensional Orthogonal Graph Drawing},
          author = {Maurizio Patrignani},
       publisher = {Springer},
            year = {2006},
           pages = {368--379},
             url = {http://gdea.informatik.uni-koeln.de/705/},
        abstract = {We introduce the 3SAT reduction framework which can be used to prove the NP-hardness of finding three-dimensional orthogonal drawings with specific constraints. We use it to show that finding a drawing of a graph whose edges have a fixed shape is NP-hard. Also, it is NP-hard finding a drawing of a graph with nodes at prescribed positions when a maximum of two bends per edge is allowed. We comment the impact of these results on the two open problems of determining whether a graph always admits a 3D orthogonal drawing with at most two bends per edge and of characterizing orthogonal shapes admitting a drawing without intersections.
    }
}