@misc{indiciae1b7a40b607ff,
  title = {Nd, O and Sr isotopic constraints on the origin of Precambrian rocks, southern Black Hills, South Dakota},
  author = {R.J. Walker and G. N. Hanson and J. J. Papike and J. R. O’Neil},
  year = {1986},
  doi = {10.1016/0016-7037(86)90230-9},
  url = {https://pubs.usgs.gov/publication/70014580},
  note = {Source identifier: 70014580}
}