@InProceedings{kn:EngVer-ConcatenationOfGraphs,
  author = 	 "J. Engelfriet and J. J. Vereijken",
  title = 	 "Concatenation of Graphs",
  booktitle = 	 "Graph-Grammars and Their Application to Computer
		  Science",
  editor = 	 "J. Cuny and H. Ehrig and G. Engels and G. Rozenberg",
  number = 	 "1073",
  series = 	 "Lecture Notes in Computer Science",
  year = 	 "1996",
  publisher =    "Springer",
  pages = 	 "368--382"
}