@Manual{Rpackage:classGraph,
  title = {classGraph: Construct Graphs of S4 Class Hierarchies},
  author = {Martin Maechler},
  year = {2015},
  note = {(partly based on code from Robert Gentleman) R package version 0.7-5},
  url = {https://CRAN.R-project.org/package=classGraph},
}

@Manual{Rpackage:graph,
  title = {graph: A package to handle graph data structures},
  author = {R. Gentleman and Elizabeth Whalen and W. Huber and S. Falcon},
  year = {2017},
  note = {R package version 1.56.0},
}

@Manual{Rpackage:Rgraphviz,
  title = {Rgraphviz: Provides plotting capabilities for R graph objects},
  author = {Kasper Daniel Hansen and Jeff Gentry and Li Long and Robert Gentleman and Seth Falcon and Florian Hahne and Deepayan Sarkar},
  year = {2017},
  note = {R package version 2.22.0},
}

