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Tôru Saitô (1976)

Czechoslovak Mathematical Journal

Tôru Saitô (1976)

Czechoslovak Mathematical Journal

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Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

J.R. De Miguel, J.C. Candeal, E. Indurâin (1996)

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