@book{1972,
	author = {Seminar on Recent developments in Variable structure systems, Economics and Biology, US-Italy, Taormina, Sicily, Aug. 29 - Sept. 2, 1977 and Mohler, R. R.},
	title = {Recent developments in variable stucture systems, economics and biology},
	publisher = {Springer-Verlag,},
	year = {1978},
	address = {Berlin:}
}