no. 3
A new compactification of the moduli space of curves
Compositio Mathematica, Tome 78 (1991) no. 3, pp. 297-313. 
@article{CM_1991__78_3_297_0,
     author = {Schubert, David},
     title = {A new compactification of the moduli space of curves},
     journal = {Compositio Mathematica},
     pages = {297--313},
     publisher = {Kluwer Academic Publishers},
     volume = {78},
     number = {3},
     year = {1991},
     zbl = {0735.14022},
     mrnumber = {1106299},
     language = {en},
     url = {www.numdam.org/item/CM_1991__78_3_297_0/}
}
Schubert, David. A new compactification of the moduli space of curves. Compositio Mathematica, Tome 78 (1991) no. 3, pp. 297-313. http://www.numdam.org/item/CM_1991__78_3_297_0/

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