@article{AM2_1995__50_1-2_137622,
     author = {W.T. Tutte},
     title = {Chromatic sums revisited.},
     journal = {Aequationes mathematicae},
     pages = {95--134},
     publisher = {mathdoc},
     volume = {50},
     number = {1-2},
     year = {1995},
     zbl = {0842.05031},
     url = {http://geodesic.mathdoc.fr/item/AM2_1995__50_1-2_137622/}
}