1. BUTLER B unpublished data.
2. Chapman, C. R., Mercury: 1 (1988).
3. Clark, B. G., Synthesis Imaging in Radio Astronomy: 9 (1989).
4. Clark, P. E., Mercury: 77 (1988).
5. CORNWELL, T.J., A METHOD OF STABILIZING THE CLEAN ALGORITHM, ASTRONOMY AND ASTROPHYSICS 121: 281 (1983).