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+/* courtesy Ian Darwin and Geoff Collyer, Softquad Inc. */

+digraph unix {

+size="6,6";

+	edge [style=bold, color=red];

+

+	"5th Edition" -> "6th Edition";

+	"5th Edition" -> "PWB 1.0";

+	"6th Edition" -> "LSX";

+	"6th Edition" -> "1 BSD";

+	"6th Edition" -> "Mini Unix";

+	"6th Edition" -> "Wollongong";

+	"6th Edition" -> "Interdata";

+	"Interdata" -> "Unix/TS 3.0";

+	"Interdata" -> "PWB 2.0";

+	"Interdata" -> "7th Edition";

+	"7th Edition" -> "8th Edition";

+	"7th Edition" -> "32V";

+	"7th Edition" -> "V7M";

+	"7th Edition" -> "Ultrix-11";

+	"7th Edition" -> "Xenix";

+	"7th Edition" -> "UniPlus+";

+	"V7M" -> "Ultrix-11";

+	"8th Edition" -> "9th Edition";

+	"1 BSD" -> "2 BSD";

+	"2 BSD" -> "2.8 BSD";

+	"2.8 BSD" -> "Ultrix-11";

+	"2.8 BSD" -> "2.9 BSD";

+	"32V" -> "3 BSD";

+	"3 BSD" -> "4 BSD";

+	"4 BSD" -> "4.1 BSD";

+	"4.1 BSD" -> "4.2 BSD";

+	"4.1 BSD" -> "2.8 BSD";

+	"4.1 BSD" -> "8th Edition";

+	"4.2 BSD" -> "4.3 BSD";

+	"4.2 BSD" -> "Ultrix-32";

+	"PWB 1.0" -> "PWB 1.2";

+	"PWB 1.0" -> "USG 1.0";

+	"PWB 1.2" -> "PWB 2.0";

+	"USG 1.0" -> "CB Unix 1";

+	"USG 1.0" -> "USG 2.0";

+	"CB Unix 1" -> "CB Unix 2";

+	"CB Unix 2" -> "CB Unix 3";

+	"CB Unix 3" -> "Unix/TS++";

+	"CB Unix 3" -> "PDP-11 Sys V";

+	"USG 2.0" -> "USG 3.0";

+	"USG 3.0" -> "Unix/TS 3.0";

+	"PWB 2.0" -> "Unix/TS 3.0";

+	"Unix/TS 1.0" -> "Unix/TS 3.0";

+	"Unix/TS 3.0" -> "TS 4.0";

+	"Unix/TS++" -> "TS 4.0";

+	"CB Unix 3" -> "TS 4.0";

+	"TS 4.0" -> "System V.0";

+	"System V.0" -> "System V.2";

+	"System V.2" -> "System V.3";

+}