the sixth international symposium on nitrogen fixation with non-legumes, ismailia-egypt, 6 - 10 september 1993 Hegazi, N.A. creator ed. Monib, M ed. Fayez, M. ed. Egypt The American University in Cairo Press 1994 1994 xix,599p. 27cm Specific techniques; apparatus, equipment,materials Soil science 631.4 NIT 9774243552