@article{VMUMM_2010_1_a4,
     author = {Yu. Yu. Druzhinin},
     title = {The linearity of metric projection operator for subspaces of $L_p$ spaces},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {30--36},
     publisher = {mathdoc},
     number = {1},
     year = {2010},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_2010_1_a4/}
}