@misc{indiciae1189c62c1bd5,
  title = {Numerical simulation of a sphere moving down an incline with identical spheres placed equally apart},
  author = {Chi-Hai Ling and Chyan-Deng Jan and Cheng-lung Chen and Hsieh Wen Shen},
  year = {1992},
  url = {https://pubs.usgs.gov/publication/70017189},
  note = {Source identifier: 70017189}
}