@article{MZ_1982__180_173178,
     author = {N.R. Wallach and A. Rocha-Caridi},
     title = {Projective {Modules} over {Graded} {Lie} {Algebras.} {I.}},
     journal = {Mathematische Zeitschrift},
     pages = {151--178},
     publisher = {mathdoc},
     volume = {180},
     year = {1982},
     zbl = {0467.17006},
     url = {http://geodesic.mathdoc.fr/item/MZ_1982__180_173178/}
}