@article{JRAM_1974__270_151491,
     author = {P.D. Morris and E.W. Cheney},
     title = {On the existence and characterization of minimal projections.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {61--76},
     publisher = {mathdoc},
     volume = {270},
     year = {1974},
     zbl = {0303.41037},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1974__270_151491/}
}