Laying out graphs using queues
SIAM Journal on Computing
Stack and Queue Layouts of Directed Acyclic Graphs: Part II
SIAM Journal on Computing
Recognizing Leveled-Planar Dags in Linear Time
GD '95 Proceedings of the Symposium on Graph Drawing
Pitfalls of Using PQ-Trees in Automatic Graph Drawing
GD '97 Proceedings of the 5th International Symposium on Graph Drawing
Separating Thickness from Geometric Thickness
GD '02 Revised Papers from the 10th International Symposium on Graph Drawing
Communicating Centrality in Policy Network Drawings
IEEE Transactions on Visualization and Computer Graphics
The geometric thickness of low degree graphs
SCG '04 Proceedings of the twentieth annual symposium on Computational geometry
Characterization of unlabeled level planar trees
GD'06 Proceedings of the 14th international conference on Graph drawing
Characterization of unlabeled level planar graphs
GD'07 Proceedings of the 15th international conference on Graph drawing
Practical level planarity testing and layout with embedding constraints
GD'07 Proceedings of the 15th international conference on Graph drawing
Minimum level nonplanar patterns for trees
GD'07 Proceedings of the 15th international conference on Graph drawing
Simultaneous geometric graph embeddings
GD'07 Proceedings of the 15th international conference on Graph drawing
Two trees which are self–intersecting when drawn simultaneously
GD'05 Proceedings of the 13th international conference on Graph Drawing
Matched drawability of graph pairs and of graph triples
Computational Geometry: Theory and Applications
On a tree and a path with no geometric simultaneous embedding
GD'10 Proceedings of the 18th international conference on Graph drawing
On graphs supported by line sets
GD'10 Proceedings of the 18th international conference on Graph drawing
A center transversal theorem for hyperplanes and applications to graph drawing
Proceedings of the twenty-seventh annual symposium on Computational geometry
On the characterization of level planar trees by minimal patterns
GD'09 Proceedings of the 17th international conference on Graph Drawing
Characterization of unlabeled radial level planar graphs
GD'09 Proceedings of the 17th international conference on Graph Drawing
Universal line-sets for drawing planar 3-trees
WALCOM'12 Proceedings of the 6th international conference on Algorithms and computation
Vertex angle and crossing angle resolution of leveled tree drawings
Information Processing Letters
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Consider a graph G with vertex set V in which each of the n vertices is assigned a number from the set {1,...,k} for some positive integer k. This assignment @f is a labeling if all k numbers are used. If @f does not assign adjacent vertices the same label, then @f forms a leveling that partitions V into k levels. If G has a planar drawing in which the y-coordinate of all vertices match their labels and edges are drawn strictly y-monotone, then G is level planar. In this paper, we consider the class of level trees that are level planar regardless of their labeling. We call such trees unlabeled level planar (ULP). Our contributions are three-fold. First, we describe which trees are ULP and provide linear-time level planar drawing algorithms for any labeling. Second, we characterize ULP trees in terms of forbidden subtrees so that any other tree must contain a subtree homeomorphic to one of these. Third, we provide a linear-time recognition algorithm for ULP trees.