Let $G$ be a simple graph. For a general edge coloring of a graph $G$ (i.e., not necessarily a proper edge coloring) and a vertex $v$ of $G$, denote by $S\left(v\right)$ the set (not a multiset) of colors used to color the edges incident to $v$. For a general edge coloring $f$ of a graph $G$, if $S\left(u\right)\ne S\left(v\right)$ for any two different vertices $u$ and $v$ of $G$, then we say that $f$ is a point-distinguishing general edge coloring of $G$. The minimum number of colors required for a point-distinguishing general edge coloring of $G$, denoted by ${\chi }_0\left(G\right)$, is called...

We prove that every planar graph with maximum degree ∆ is strong edge (2∆−1)-colorable if its girth is at least 40 [...] +1. The bound 2∆−1 is reached at any graph that has two adjacent vertices of degree ∆.

An edge-colored graph $G$ is proper connected if every pair of vertices is connected by a proper path. The proper connection number of a connected graph $G$, denoted by $\mathrm{pc}\left(G\right)$, is the smallest number of colors that are needed to color the edges of $G$ in order to make it proper connected. In this paper, we obtain the sharp upper bound for $\mathrm{pc}\left(G\right)$ of a general bipartite graph $G$ and a series of extremal graphs. Additionally, we give a proper $2$-coloring for a connected bipartite graph $G$ having $\delta \left(G\right)\ge 2$ and a dominating cycle...