2 citations · 2 across the 2 of their papers we have counts for
6 papers · 1 filter
Concepts of signed graph coloring
Eckhard Steffen, Alexander Vogel
This paper surveys recent development of concepts related to coloring of signed graphs. Various approaches are presented and discussed.
Flows on signed graphs without long barbells
You Lu, Rong Luo, Michael Schubert +2
Many basic properties in Tutte's flow theory for unsigned graphs do not have their counterparts for signed graphs. However, signed graphs without long barbells in many ways behave…
Fractional matchings, component-factors and edge-chromatic critical graphs
Antje Klopp, Eckhard Steffen
The first part of the paper studies star-cycle factors of graphs. It characterizes star-cycle factors of a graph and proves upper bounds for the minimum number of -com…
Remarks on planar edge-chromatic critical graphs
Ligang Jin, Yingli Kang, Eckhard Steffen
The only open case of Vizing's conjecture that every planar graph with is a class 1 graph is . We give a short proof of the following statement: there is no 6-criti…
On measures of edge-uncolorability of cubic graphs: A brief survey and some new results
M. A. Fiol, G. Mazzuoccolo, E. Steffen
There are many hard conjectures in graph theory, like Tutte's 5-flow conjecture, and the 5-cycle double cover conjecture, which would be true in general if they would be true for c…
Signed graphs with two negative edges
Edita Rollová, Michael Schubert, Eckhard Steffen
The presented paper studies the flow number of flow-admissible signed graphs with two negative edges. We restrict our study to cubic graphs, because for each non-c…