@book{33375,
	author = {Reyn, John. and SpringerLink (Online service)},
	title = {Phase Portraits of Planar Quadratic Systems},
	publisher = {Springer US,},
	year = {2007.},
	series = {Mathematics and Its Applications ;},
	address = {Boston, MA :},
	url = {http://dx.doi.org/10.1007/978-0-387-35215-2}
}