@inbook {LeibVava,
	title = {Analysis of polynomial approximation algorithms for constraint expressions},
	booktitle = {Theoretical Computer Science: 6th GI conference, Dortmund},
	series = {Lecture Notes in Computer Science},
	volume = {145},
	year = {1982},
	publisher = {Springer Verlag},
	organization = {Springer Verlag},
	address = {Berlin},
	author = {K. J. Lieberherr and S. A. Vavasis},
	editor = {A. B. Cremers and H. P. Kriegel}
}