@article{10_4064_fm_65_1_95_127,
     author = {John Doner and Alfred Tarski},
     title = {An extended arithmetic of ordinal numbers},
     journal = {Fundamenta Mathematicae},
     pages = {95--127},
     publisher = {mathdoc},
     volume = {65},
     number = {1},
     year = {1969},
     doi = {10.4064/fm-65-1-95-127},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-65-1-95-127/}
}