@article{10_4064_fm_81_1_49_56,
     author = {J. Hickman},
     title = {A problem on series of ordinals},
     journal = {Fundamenta Mathematicae},
     pages = {49--56},
     publisher = {mathdoc},
     volume = {81},
     number = {1},
     year = {1973},
     doi = {10.4064/fm-81-1-49-56},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-81-1-49-56/}
}