Q: in proving some of the results in his thesis riemann used a variational principle which he was later to call the dirichlet principle since he had learnt it from dirichlet 's lectures in berlin.

A: In proving some of the results in his thesis Riemann used a variational principle which he was later to call the Dirichlet Principle since he had learnt it from Dirichlet 's lectures in Berlin.
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Q: youtube support is provided by this plugin also comes in spanish.

A: Youtube support is provided by this plugin also comes in Spanish.
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Q: imitation precious and semi-precious stones of glass, cut and mechanically polished (excl. articles thereof)

A:
Imitation precious and semi-precious stones of glass, cut and mechanically polished (excl. articles thereof)
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