'graph Heawood {
 graph [ rankdir="TB" ]
 edge [ color="black" ]
 node [ color="black" fontname="Arial" height="0.500000" label="\\N" shape="circle" width="0.50000" ]
 "0" -- "1"
 "1" -- "2"
 "2" -- "3"
 "3" -- "4"
 "4" -- "5"
 "5" -- "6"
 "6" -- "7"
 "7" -- "8"
 "8" -- "9"
 "9" -- "10"
 "10" -- "11"
 "11" -- "12"
 "12" -- "13"
 "13" -- "0"
 "0" -- "5" [ len="2.5" ]
 "2" -- "7" [ len="2.5" ]
 "4" -- "9" [ len="2.5" ]
 "6" -- "11" [ len="2.5" ]
 "8" -- "13" [ len="2.5" ]
 "10" -- "1" [ len="2.5" ]
 "12" -- "3" [ len="2.5" ]
}
'
