How to Draw a Series-Parallel Digraph.

Paola Bertolazzi Robert F. Cohen Giuseppe Di Battista Roberto Tamassia Ioannis G. Tollis How to Draw a Series-Parallel Digraph. 385-402 1994 4 Int. J. Comput. Geometry Appl. 4 db/journals/ijcga/ijcga4.html#BertolazziCBTT94 http://dx.doi.org/10.1142/S0218195994000215