@article{TMF_1974_18_3_a12,
     author = {K. S. Matviichuk},
     title = {Reduced density matrices with nonzero boundary conditions in the case of a~hard core},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {410--426},
     publisher = {mathdoc},
     volume = {18},
     number = {3},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1974_18_3_a12/}
}