Why has the do-it-yourself package of this text not used XML? The main problem is that the parsers are not yet standardized. For example, for unix the C++ computer by itself is no longer sufficient; one needs to add some additional software. We expect the situation to be similar under other operating systems. In addition, the situation with parsers still is in a state of flux. That is, a parser that works today may not work any longer is a couple of months from now. For all other pieces of our package, we expect that it will work on standard systems for many years into the future.
For all those reasons, this text does not use XML files, but standard text files. However, there is a public domain version of our work, currently at [[where]], which uses XML and which can be used as a starting point for further development.