@misc{indiciae5c6563f08ea8,
  title = {Ancient engineering geology projects in China; A canal system in Ganzu province and trenches along the Great Wall in Ningxia Hui Autonomous Region},
  author = {R. E. Wallace and R.C. Bucknam and Thomas C. Hanks},
  year = {1994},
  doi = {10.1016/0013-7952(94)90003-5},
  url = {https://pubs.usgs.gov/publication/70017006},
  note = {Source identifier: 70017006}
}