Figure 5

Example rules expressed in XSLT: an atom must have an id attribute and the value of the id must be unique among the ids of all the atoms in the eldest containing parent molecule. The cml prefix is bound to http://www.xml-cml.org/schema and the report prefix is bound to http://www.xml-cml.org/report/. The error reporting has been simplified for clarity (the location attribute is omitted).