Generating structured flow diagrams: the nature of unstructuredness
M. Howard Williams · The Computer Journal · 1977
Various methods have been put forward by different authors for converting an ‘unstructured flow diagram’ into an equivalent ‘structured’ one. This paper examines the basic flow diagram sub-structures, the presence of which in a flow diagram causes the flow diagram to be unstructured, and proves that these are the only structures which lead to unstructuredness.