@book{60501,
	author = {Karlqvist, Anders (Ed.) and Lundqvist, Lars (Ed.)},
	title = {Spatial interaction theory and planning models},
	publisher = {North-Holland},
	year = {1978},
	address = {Amsterdam},
	note = {Papers presented at an international research conference in Bastad, Sweeden, August 29-31, 1977 organised by Research Group for Urban and Regional Planning, Department of Mathematics, Royal Institute of Technology, Stockholm}
}