@article{10_14708_ma_v7i15_1477,
     author = {Stanis{\l}aw Lewanowicz},
     title = {Minimal projective operators},
     journal = {Mathematica Applicanda},
     pages = { 25--46},
     publisher = {mathdoc},
     volume = {7},
     number = {15},
     year = {1979},
     doi = {10.14708/ma.v7i15.1477},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/ma.v7i15.1477/}
}