Basically the same feature of including files is also available for use in the
.rkh files. At any place in these files you can place an <include> tag as shown below. The effect is that the entire contents of that XML file (to be precise: everything within the <document> tag of that file) is included verbatim at this point in the file. Note that you can only include another XML file.
file is the filename relative to the directory the current file is located in.