First user-interaction seminar / Proceedings of the first user-interaction seminar 19-20 December, 1980 held at National Remote Sensing Agency Balanagar, Hyderabad-500 037 India - Secunderabad: National Remote Sensing Agency, 1980 - 66p. Subjects--Topical Terms: Proceedings Universal Decimal Class. No.: 528.71.004(082.2) / M0