Seok-Hee Hong, Peter Eades and Jonathan Hillman, Linkless Symmetric Drawings of Series Parallel Digraphs, Computational Geometry: Theory and Applications, 29(3), pp. 191-222, 2004, Elsevier.
In this paper,we present a linear time algorithmfor constructing linkless drawings of series parallel digraphswith
maximum number of symmetries. Linkless drawing in three dimensions is a natural extension to planar drawing
in two dimensions. Symmetry is one of the most important aesthetic criteria in graph drawing. More specifically,
we present two algorithms: a symmetry finding algorithm which finds maximum number of three dimensional
symmetries, and a drawing algorithm which constructs linkless symmetric drawings of series parallel digraphs in