@misc{indiciaeba0e4e6e85de,
  title = {The effect of varying task difficulty on subjective workload},
  author = {Yeh, Y.-Y. and Wickens, C. D. and Hart, S. G.},
  year = {1985},
  url = {https://ntrs.nasa.gov/citations/19860049070},
  note = {Source identifier: 19860049070}
}