Volume 21 Issue 1, 1–137
Volume 20 Issue 2+3, 63–634 Issue 1, 1–61
Volume 19 Issue 4, 137–181 Issue 3, 95–135 Issue 2, 47–94 Issue 1, 1–46
Volume 17 Issue 3, 189–249 Issue 2, 77–188 Issue 1, 1-75
[21] Originally published in C. R. Acad. Sci. Paris 239 (1954), 850–852. Reused with permission.
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