43 citations · 166 across the 37 of their papers we have counts for
6 papers · 1 filter
The chromatic spectrum of signed graphs
Yingli Kang, Eckhard Steffen
The chromatic number of a signed graph is the smallest number for which there is a function such that $c(v) \not= σ(e) c(…
Circular coloring of signed graphs
Yingli Kang, Eckhard Steffen
Let ( be two positive integers. We generalize the well studied notions of -colorings and of the circular chromatic number to signed graphs. This imp…
Unions of 1-factors in -graphs and overfull graphs
Ligang Jin, Eckhard Steffen
We prove lower bounds for the fraction of edges of an -graph which can be covered by the union of 1-factors. The special case yields some known results for cubic graph…
Choosability in signed planar graphs
Ligang Jin, Yingli Kang, Eckhard Steffen
This paper studies the choosability of signed planar graphs. We prove that every signed planar graph is 5-choosable and that there is a signed planar graph which is not 4-choosable…
Face-degree bounds for planar critical graphs
Ligang Jin, Yingli Kang, Eckhard Steffen
The only remaining case of a well known conjecture of Vizing states that there is no planar graph with maximum degree 6 and edge chromatic number 7. We introduce parameters for pla…
Petersen cores and the oddness of cubic graphs
Ligang Jin, Eckhard Steffen
Let be a bridgeless cubic graph. Consider a list of 1-factors of . Let be the set of edges contained in precisely members of the 1-factors. Let be…