@book{13167,
	author = {Coddington, E. A. and Snoo, Hendrik S. V. de. and Snoo, Hendrik S. V. de ;jt. auth.},
	title = {Regular boundary value problems associated with Paris of ordinary differential expressions},
	publisher = {Springer-Verlag},
	year = {1981},
	series = {Lecture notes in Mathematics},
	address = {Berlin}
}