digraph flow {

	subgraph {
		rankdir="LR";
		rank=same;
		cnc [label="sch-rnd\nconcrete model"]
		csv1 [label="sch-rnd\nattbl_csv export"]
		extedit [label="external editor\ne.g. spreadsheet" shape=box]
		csv2 [label="sch-rnd\nattbl_csv import"]
	}

	cnc -> csv1
	csv1 -> extedit
	extedit -> csv2
	csv2 -> cnc

}
