1. Achong, A., Stahl, P.A., and Nyack, C.: 1903, Solar Phys. 88, 137.
2. Achong, A. and Stahl, P.A.: 1984, Solar Phys. 92, 259.
3. Bulmer, M.G.: 1979, Principles of Statistics, Dover Publications, New York, New York, p. 151.
4. Choi, S.C.: 1978, Introductory Applied Statistics in Science, Prentice-Hall, Englewood Cliffs, New Jersey, p. 101.
5. Coffey, H.: 1980, -81, Solar Geophysical Data, Part I, Part II, U.S. Dept. of Commerce, Boulder, Colorado.