Metric perturbations in two-field inflation.

@article{GarcaBellido1996MetricPI,
  title={Metric perturbations in two-field inflation.},
  author={Garc{\'i}a-Bellido and Wands},
  journal={Physical review. D, Particles and fields},
  year={1996},
  volume={53 10},
  pages={5437-5445}
}