On Minimum Area Planar Upward Drawings of Directed Trees and Other Families of Directed Acyclic Graphs.

Fabrizio Frati On Minimum Area Planar Upward Drawings of Directed Trees and Other Families of Directed Acyclic Graphs. 251-271 2008 18 Int. J. Comput. Geometry Appl. 3 http://dx.doi.org/10.1142/S021819590800260X db/journals/ijcga/ijcga18.html#Frati08