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Applied Mathematics E-Notes [electronic only]

Li, Ai-Jun, Wang, Xue-Min, Chen, Chao-Ping (2006)

JIPAM. Journal of Inequalities in Pure & Applied Mathematics [electronic only]

Qi, Feng (2000)

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Anders Lundberg (1985)

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K.D. jr. Magill, B.B. Baird (1979)

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