Published in: Bulletin of the American Mathematical Society, 71 (1965) 5, Seite 737-742

Published in: Memoirs of the Faculty of Science, Kyushu University. Series A, Mathematics, 14 (1960) 1, Seite 45-49

Published in: Pacific Journal of Mathematics, 80 (1979) 2, Seite 297-303

Published in: Kodai Mathematical Journal, 17 (1965) 4

Published in: Proceedings of the Japan Academy, Series A, Mathematical Sciences, 28 (1952) 1

Published in: Kodai Mathematical Journal, 3 (1951) 1-2

Published in: Archive for History of Exact Sciences, 64 (2010) 1, Seite 1-73

Published in: Archive for History of Exact Sciences, 64 (2010) 1, Seite 1-73