@article{RSMUP_1985__73__49_0,
     author = {Hausen, Jutta and Johnson, Johnny A.},
     title = {On the existence of projective and quasi-projective covers},
     journal = {Rendiconti del Seminario Matematico della Universit\`a di Padova},
     pages = {49--54},
     publisher = {Seminario Matematico of the University of Padua},
     volume = {73},
     year = {1985},
     mrnumber = {799896},
     zbl = {0571.16015},
     language = {en},
     url = {http://www.numdam.org/item/RSMUP_1985__73__49_0/}
}