GraphViz

<graphviz> digraph G {

 /* Industries */
 /* Source */
 subgraph source {

node [color=palegreen2, style=filled];

   "Propriedades" [URL="Coal Mine"];
   "Expoentes" [shape=box] [URL="Farm"];
 }

 subgraph main {

node [color=green, style=filled];

   "Expoentes" [URL="Town"];
 }

/* subgraph standalone {

node [color=lightblue, style=filled];

   "Banks" [URL="Bank"]
 } */

 subgraph convert {
   "Factories" [URL="Factory"];
   "Oil Refineries" [URL="Oil Refinery"];
   "Sawmills" [URL="Sawmill"];
   "Steel Mills" [URL="Steel Mill"];
 }

 subgraph sink {

node [color=lightgrey, style=filled];

   "Power Stations" [URL="http://wiki.sj.ifsc.edu.br/index.php/Usu%C3%A1rio:Maria.t"]
 }
  

 /* Cargo types and connections */
 "Coal Mines" -> "Sawmills" [label="TESTE"];
 "Forests" -> "Sawmills" [label="Wood"];
 "Sawmills" -> "Towns" [label="Goods"];

 "Iron Ore Mines" -> "Steel Mills" [label="Iron Ore"];
 "Steel Mills" -> "Factories" [label="Steel"];

 "Farms" -> "Factories" [label="Grain"];
 "Farms" -> "Factories" [label="Livestock"];

 "Factories" -> "Towns" [label="Goods"];

 "Oil Wells" -> "Oil Refineries" [label="Oil"];
 "Oil Rigs" -> "Oil Refineries" [label="Oil"];
 "Oil Refineries" -> "Towns" [label="Goods"];

 "Coal Mines" -> "Power Stations" [label="Coal"];
 
 "Oil Rigs" -> "Towns" [label="Passengers"];
 "Oil Rigs" -> "Oil Rigs" [label="Passengers"];
 "Towns" -> "Oil Rigs" [label="Mail"];
 "Towns" -> "Oil Rigs" [label="Passengers"];
 "Towns" -> "Towns" [label="Mail"];
 "Towns" -> "Towns" [label="Passengers"];

 "Banks" -> "Banks" [label="Valuables"]

} </graphviz>