A word, phrase, or sentence that directs the reader to related information in the same document (or, in the case of online content, perhaps a different document), whether said document is an article or a book, is called a cross-reference. This post discusses best practices in employing cross-references.
In printed or online content, a cross-reference is a text element that introduces the reader to a subsequent element of content, whether text or one or more graphic elements. For example, an observation or assertion may be followed by a statement such as “See further discussion in chapter 6” or “See the columns labeled ‘Cause’ and ‘Effect’ in figure 1 below.”
Note a couple of details about these examples: First, neither example uses page numbers to locate the cross-reference; this is because, in the case of a printed document, pagination may change when the content is reprinted or is posted online. (Also, the designations for types of content—chapter and figure—are not capitalized, nor are similar terms such as appendix, part, and table, and numbers are always styled as numerals, not spelled out.) For the same reason, avoid directions such as “See next page”; write “See below,” instead, especially to direct the reader’s attention to a figure or table.
Cross-references can also refer to preceding elements, either by specific references or by calling attention to, for example, “the abovementioned factors” or “the aforementioned locations,” “the foregoing discussion,” or “the participants mentioned above.” General references similar to these seldom precede their referents, and equivalents of abovementioned and aforementioned that replace the first half of each word with below and after are not valid words, nor is aftergoing. (Prementioned is a real world, but I have never seen it used in this context.)
On a related note, it is essential to check all cross-references in a given piece of content. Any references to the title of the overall content itself that appear in the content should match, and the writer, and/or an editor or proofreader, should verify that all elements listed in the table of contents—part and chapter titles and any headings and subheadings—and related lists of such elements as figures and tables should be verified against the lists. (At the proofreading stage, page numbers in the table of contents and similar lists, which are entered in the electronic file from which the publication is created only after the text is paginated, should also be cross-checked against the respective pages.)
In addition, all cross-references discussed in the foregoing discussion should be checked to make sure that, for example, when figure 5 is mentioned in regard to a certain topic, fact, or data point, that information appears in figure 5. Likewise, a caption for an illustration or a photograph, or a reference to the image in the running text, should be inspected to verify that it correctly identifies what is shown in the image. Chapter numbers and other identifying information should be cross-checked in the proofreading stage as well; such indicators may have been changed at some point because, for example, two chapters have been combined, one has been deleted, or a new one has been inserted.
At the same time, or in a separate review, spelling or treatment of terms in the text should be checked to ensure that it matches those shown in figures. For example, if a table with a list of names refers to someone as Smythe, but the text uses Smyth, the correct choice should be verified and the error corrected, or if a map identifies the most populous city in India as Bombay but the text uses the newer standard form Mumbai (whether in reference to the map or in isolation), the map should be relabeled, or replaced with one that uses the modern form.
Also, when footnotes or endnotes are employed, text that prompts a note should be checked against the wording of the note to ensure that they are pertinent to each other, and when a citation is noted, it should be checked against a list of references to make sure, first, that an entry for each citation is listed and, second, that the information in the citation (for example, a last name and the year of publication) matches the information in the references. In a separate step, the references should be cross-checked against citations to make sure that every reference in the list has one or more corresponding citations; reference entries without a citation should be deleted.
URLs and links to email addresses should also be verified, and links should be tested to ensure that the destination of the link is correct and correctly identified.