Technical reports and instructions often require cross-references—those pointers to other places in the same document or to other information sources where related information can be found. (For quick reference, see Summary of Cross-Reference Rules.)

A cross-reference can help readers in a number of different ways:

Related information is the hardest area to explain because ultimately everything is related to everything else—there could be no end to the cross-references. But here's an example from DOS—that troll that lurks inside PC-type computers and supposedly helps you. There are several ways you can copy files: the COPY command, the DISKCOPY command, and XCOPY command. Each method offers different advantages. If you were writing about the COPY command, you'd want cross-references to these other two so that readers could do a bit of shopping around.

Of course, the preceding discussion assumed cross-references within the same document. If there is just too much background to cover in your document, you can cross-reference some external website, book, or article that does provide that background. That way, you are off the hook for having to explain it all!

Now, a decent cross-reference consists of several elements:

These guidelines are shown in the following illustration. Notice in that illustration how different the rules are when the cross-reference is "internal" (that is, to some other part of the same document) compared to when it is "external" (to information outside of the document).


Examples of cross-references. Internal cross-references are cross-references to other areas within your same document; external ones are those to information resources external to your document.

Summary of Cross-Reference Rules

  • If your cross-reference contains the title of a book, periodical, or report, italicize that title.
  • If your cross-reference contains the title of an article or the title of a chapter or heading, enclose that title in quotation marks.
  • If your cross-reference contains something like Figure 1. or Table 2., do not use italics or quotation marks on that item.
  • If your cross-reference contains the title of a figure or table, enclose that title in quotation marks.
  • If your cross-reference contains a brief indication of the contents of a chapter, use lowercase; do not use italics or quotation marks.
  • If your cross-reference contains a reference to a specific page elsewhere in the same document, include the page number unless that page is the beginning of a chapter (in which case just cite the chapter number).
  • If your cross-reference contains a reference to a specific page in some other document, do not include the page number.
  • If your cross-reference contains a reference to a chapter in either the same or some other document, include the chapter number but prefer a brief indication of the contents of that chapter rather than quoting the title.