RHOG: A Refinement-Operator Library for Directed Labeled Graphs
  This document provides the foundations behind the functionality provided by
the $\rho$G library (https://github.com/santiontanon/RHOG), focusing on the
basic operations the library provides: subsumption, refinement of directed
labeled graphs, and distance/similarity assessment between directed labeled
graphs. $\rho$G development was initially supported by the National Science
Foundation, by the EAGER grant IIS-1551338.
