Slovenija Abstract A vertex-transitive graph is said to be 1 2-transitive if its automor-phism group is vertex and edge but not arc-transitive. Some recent results on 1 2-transitive graphs are given, a few open problems proposed , and possible directions in the research of the structure of these graphs discussed. 1 In the beginning Throughout this paper graphs are simple and, unless otherwise s...

The notions of (transitive) soft d-algebras, soft edge d-algebras, soft d-algebras, soft dideals, soft d-ideals, soft d-ideals, and d-idealistic (d-idealistic, or d-idealistic) soft dalgebras are introduced. Also, their related properties are surveyed. © 2008 Elsevier Ltd. All rights reserved.

We show that every transitive hyperbolic set on a surface is included in a locally maximal hyperbolic set.

We classify the transitive and co-transitive blocking sets in a finite Desarguesian plane.