document-centered approach to indexing relies on the indexer's analysis
of a number of document attributes as the basis for establishing the document's subject matter.
The exact attributes that indexing guidelines or textbooks recommend that the indexer examine varies, but archetypical examples are: the title, the abstract, the table of contents, chapter headings, chapter subheadings, preface, introduction, foreword, the text itself, bibliographical references, index entries, illustrations, diagrams, and tables and their captions.