@article{IM_1986__85_143377,
     author = {D. Zagier and J. Harer},
     title = {The {Euler} characteristic of the moduli space of curves.},
     journal = {Inventiones mathematicae},
     pages = {457--486},
     publisher = {mathdoc},
     volume = {85},
     year = {1986},
     zbl = {0616.14017},
     url = {http://geodesic.mathdoc.fr/item/IM_1986__85_143377/}
}