cropping pattern changes and efficiency gains in semi-arid tropics Gulati, Ashok creator Kelley, Tim text xx New Delhi Oxford University Press 1999 9999 monographic und xvi, 296p+Tab+Fig. Ashok Gulati Agriculture-India; Cropping systems-India; Produce trade-Government policy; Arid regions agriculture 382.4130954 G971T 019-564865-X NITIL 190327