6. The method of claim 4 , wherein at least some of the document elements include respectively a number of identifiers, each of the identifiers being assigned to one of the at least some of the document elements.
6. The method of claim 4 , wherein at least some of the document elements include respectively a number of identifiers, each of the identifiers being assigned to one of the at least some of the document elements. 7. The method of claim 6 , wherein some of the identifiers are one or more of numerals and alphabets.