@article{MET_1991__38_2_176346,
     author = {S. Gupta and S. Kageyama},
     title = {Type {S} {Designs} with {Nested} {Rows} and {Columns.}},
     journal = {Metrika},
     pages = {195--202},
     publisher = {mathdoc},
     volume = {38},
     number = {2},
     year = {1991},
     zbl = {0735.62073},
     url = {http://geodesic.mathdoc.fr/item/MET_1991__38_2_176346/}
}