Melanopsin: an exciting photopigment

@article{Hankins2008MelanopsinAE,
  title={Melanopsin: an exciting photopigment},
  author={Mark W. Hankins and Stuart N. Peirson and Russell G. Foster},
  journal={Trends in Neurosciences},
  year={2008},
  volume={31},
  pages={27-36}
}

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...

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