selected papers from the Fourth International Conference of the International Federation of Organic Agriculture Movements, Cambridge, Massachusetts, August 18 to 20, 1982 Lockeretz, William International Federation of Organic Agriculture Movements text monographic xii, 426 pages : illustrations ; 25 cm Agricultural conservation Agricultural ecology Agriculture Organic farming 630 IIR 1999 C111 Or. 0030628636 9780030628634