Your search returned the following 4 documents:

4. Pitfalls of using PQ-Trees in Automatic graph Drawing
   Michael Jünger, Sebastian Leipert, and Petra Mutzel
   In: Proceedings of the 5th Symposium on Graph Drawing (GD-97), Rome, Italy, September, 1997, 1997, 193-204
   
3. A Note on Computing a Maximal Planar Subgraph using PQ-Trees
   Michael Jünger, Sebastian Leipert, and Petra Mutzel
   IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems 17 (7): 609-612, 1998
   
2. AGD: A Library of Algorithms for Graph Drawing
   Petra Mutzel, Carsten Gutwenger, Ralf Brockenauer, Sergej Fialko, Gunnar W. Klau, Michael Krüger, Thomas Ziegler, Stefan Näher, David Alberts, Dirk Ambras, Gunter Koch, Michael Jünger, Christoph Buchheim, and Sebastian Leipert
   In: Proceedings of the 6th International Symposium on Graph Drawing (GD-98), Montréal, Canada, August 13 - 15, 1998, 456-457
   
1. Level Planarity Testing in Linear Time
   Michael Jünger, Sebastian Leipert, and Petra Mutzel
   In: Proceedings of the 6th International Symposium on Graph Drawing (GD-98), Montreal, Canada, August 13-15, 1998, 224-237