Frequency of Occurrence of Wars and other Fatal Quarrels

@article{Richardson1941FrequencyOO,
  title={Frequency of Occurrence of Wars and other Fatal Quarrels},
  author={L. F. Richardson},
  journal={Nature},
  year={1941},
  volume={148},
  pages={598-598}
}
IN order to investigate the causes of wars by counting occurrences, let the magnitude of any war be denned to be the logarithm, to the base ten, of the number of persons who died because of that quarrel. This definition has the advantage that it applies, not only to what are ordinarily called wars, but also to all kinds of fatal quarrels, including insurrections, frontier incidents, riots and murders.