@incollection{deitmar2005schemes,
  title={Schemes over$backslash$  mathbb ${$F$}$ _1},
  author={Deitmar, Anton},
  booktitle={Number fields and function fields—two parallel worlds},
  pages={87--100},
  year={2005},
  publisher={Springer}
}

Another problem: google scholar gives me this:
@article{kurokawa2005zeta,
  title={Zeta functions over $$backslash$ mathbf ${$F$}$ _1$},
  author={Kurokawa, Nobushige and others},
  journal={Proceedings of the Japan Academy, Series A, Mathematical   Sciences},
  volume={81},
  number={10},
  pages={180--184},
  year={2005},
  publisher={The Japan Academy}
}

title={Schemes over {$mathbb{F}_1$}},

title={Zeta functions over {$mathbf{F}_1$}},