@article{10_4064_fm_41_1_38_41,
     author = {V. Balachandran},
     title = {A characterization of {\ensuremath{\Sigma}\ensuremath{\Delta}-rings} of subsets},
     journal = {Fundamenta Mathematicae},
     pages = {38--41},
     publisher = {mathdoc},
     volume = {41},
     number = {1},
     year = {1955},
     doi = {10.4064/fm-41-1-38-41},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-41-1-38-41/}
}