@book{93757,
	author = {Symposium of the American Society of Agronomy and Soil Science Society of America, Illinois, Nov.1974.},
	title = {International and national outlook the necessity for efficient nutrient utilization; proceedings.},
	publisher = {ASA & SSSA},
	year = {1975},
	series = {ASA special publication; no.25},
	address = {Wisconsin}
}