1. Cauzzi, G., Smaldone, L. A., Balasubramaniam, K. S., Keil, S.L.: 1993, Solar Phys. 146, 207
2. Hayes, J. R., Fraeman, M. E., Williams, R. L., Zaremba, T.: 1987, in Proc. 2nd Intl. Conf. Architect. Support Prog. Lang, & Oper. Syst., IEEE, p. 42
3. Hughes, D.: 1988, Aviation Week and Space Technology March 7, 44
4. Jefferies, J. T., Mickey, D. L.: 1991, Astrophys. J. 372, 694
5. Nystrom, G, Cheimets, P., Couvault, C., Grindlay, J., Coyle, L., Licata, F., Kuosmanen, V., 1992, in Symp. Thirty Years of Scientific Ballooning in India, Hyderabad