This paper is devoted to the study of particular geometrically defined intersection classes of graphs. Those were previously studied by Magnant and Martin, who proved that these graphs have arbitrary large chromatic number, while being triangle-free. We give several structural properties of these graphs, and we raise several questions.

翻译：本文致力于研究特定几何定义的图相交类。这些图此前由Magnant和Martin研究，他们证明了这些图具有任意大的色数，同时不含三角形。我们给出了这些图的若干结构性质，并提出了几个问题。