1. Canfield, R. C., Fan, Y., Leka, K. D., McClyment, A. N., Wuelser, Lites, B. W., and Zirin, H.: 1991, in L. J. November (ed.),Solar Polarimetry, Summer Workshop, p. 296.
2. Gary, G. A. and Hagyard, M. J.: 1990,Solar Phys. 126, 21.
3. Hagyard, M. J., Smith, J. B., Jr., Teuber, D., and West, E. A.: 1984,Solar Phys. 91, 115.
4. Wang, H. and Lin, Y.: 1992, in H. Zirin, G. Ai, and H. Wang (eds.), ?The Magnetic and Velocity Fields of Solar Active Regions?,IAU Colloq. 141, 461.
5. Wang, J.: 1992, in H. Zirin, G. Ai, and H. Wang (eds.), ?The Magnetic and Velocity Fields of Solar Active Regions?,IAU Colloq. 141, 425.