@article{10_4064_ap_15_1_57_76,
     author = {W. Bach},
     title = {A solution of the problem of four limits},
     journal = {Annales Polonici Mathematici},
     pages = {57--76},
     publisher = {mathdoc},
     volume = {15},
     number = {1},
     year = {1964},
     doi = {10.4064/ap-15-1-57-76},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-15-1-57-76/}
}