@article{MM2_1991__70_1_155600,
     author = {Silvio Greco and Grazia Raciti},
     title = {Gap orders of rational functions on plane curves with few singular points.},
     journal = {Manuscripta mathematica},
     pages = {441--447},
     publisher = {mathdoc},
     volume = {70},
     number = {1},
     year = {1991},
     zbl = {0733.14014},
     url = {http://geodesic.mathdoc.fr/item/MM2_1991__70_1_155600/}
}