@misc{almenara2018absolute,
  title={Absolute densities in exoplanetary systems: photodynamical modelling of Kepler-138},
  author={J. M. Almenara and R. F. Díaz and C. Dorn and X. Bonfils and S. Udry},
  year={2018},
  eprint={1805.12520},
  archivePrefix={arXiv},
  primaryClass={astro-ph.EP},
  doi={10.1093/mnras/sty1050},
  url={https://arxiv.org/abs/1805.12520}
}