@misc{indiciaea0ea921d84d8,
  title = {The Niger Delta petroleum system; Niger Delta Province, Nigeria, Cameroon, and equatorial Guinea, Africa},
  author = {Michele L. Tuttle and Ronald R. Charpentier and Michael E. Brownfield},
  year = {1999},
  doi = {10.3133/ofr9950h},
  url = {https://pubs.usgs.gov/publication/ofr9950H},
  note = {Source identifier: ofr9950H}
}