15
Acknowledgements
We would like to thank M. Norman, Tom Timusk,
Dmitri Basov, Chris Homes, Nicole Bontemps, Andres
Santander-Syro, Ricardo Lobo, Dirk van der Marel, A.
Boris, E. van Heumen, A. B. Kuzmenko, L. Benfato, and
F. Marsiglio for many discussions concerning the infrared
conductivity and optical integrals and thank A. Boris, E.
van Heumen, J. Hirsch, and F. Marsiglio for the com-
ments on the manuscript. The work was supported by
nsf-dmr 0906953.
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