@misc{indiciaee340c7cb5d4f,
  title = {A statistical study of active regions 1967-1981},
  author = {Tang, F. and Howard, R. and Adkins, J. M.},
  year = {1984},
  url = {https://ntrs.nasa.gov/citations/19840056747},
  note = {Source identifier: 19840056747}
}