Complementary variational principles for a general class of diffusion problems are presented. The theory is illustrated by the electrostatic field and it is shown that Dirichlet's and Thomson's ...

We present an inequality for fractional derivatives related to the Leibniz rule that not only answers positively a conjecture raised by J. I. Diaz, T. Pierantozi, and L. Vázquez but also helps us to ...

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