@misc{indiciae0afe3d393295,
  title = {First early Mesozoic amber in the Western Hemisphere},
  author = {R. J. Litwin and S.R. Ash},
  year = {1991},
  doi = {10.1130/0091-7613(1991)019<0273:femait>2.3.co;2},
  url = {https://pubs.usgs.gov/publication/70016766},
  note = {Source identifier: 70016766}
}