@misc{indiciae1741a59f38a7,
  title = {Documentation for the “XT3D” option in the Node Property Flow (NPF) Package of MODFLOW 6},
  author = {Alden M. Provost and Christian D. Langevin and Joseph D. Hughes},
  year = {2017},
  doi = {10.3133/tm6a56},
  url = {https://pubs.usgs.gov/publication/tm6A56},
  note = {Source identifier: tm6A56}
}