@article { WS:2001,
	title = {Detection and Visualization of Closed Streamlines in Planar Flows},
	journal = {IEEE Transactions on Visualization and Computer Graphics},
	volume = {7},
	number = {2},
	year = {2001},
	pages = {165 {\textendash} 172},
	author = {Wischgoll, T. and Gerik Scheuermann}
}
