@misc{indiciaecb8db5015b84,
  title = {American species of Operculina and Heterostegina and their faunal relations; A new species of Orthophragmina from Louisiana},
  author = {J.A. Cushman},
  year = {1921},
  doi = {10.3133/pp128e},
  url = {https://pubs.usgs.gov/publication/pp128E},
  note = {Source identifier: pp128E}
}