XML Schema Normalization Design
Two kinds of problems in designing XML schema are analyzed and the valid structure and well structure in structural level of XML normalization are defined. A valid-structured XML schema guarantees that it can be instanced, and well-structural XML schema guarantees that all the elements in it are significant. Based on the analysis of element relationship graph, the judgment method of valid structure and well structure is put forward and some theorems are presented.
H. L. Zheng et al., "XML Schema Normalization Design", Applied Mechanics and Materials, Vols. 58-60, pp. 2345-2350, 2011