1. Schroeer, D. Am. J. Phys. 51, 465 (1983).
2. Richardson, L.F. Statistics of Deadly Quarrels (Boxwood, Pittsburgh, 1960).
3. Richardson, L.F. Arms and Insecurity (Boxwood, Pittsburgh, 1960).
4. Kaye, J.D., Air Force Coll. 81, 81–89, (1962).
5. Kaye, J.D. & Lindsay, G.R. Nature 227, 696–697 (1970).