@article{mahard_1963, 
  title={Geology and Geography (E)}, 
  volume={139}, 
  DOI={10.1126/science.139.3555.635-a}, 
  number={3555}, 
  publisher={American Association for the Advancement of Science (AAAS)}, 
  author={Mahard}, 
  year={1963}, 
  month={Feb}
  }