We have used the usual multimedia techniques typical of Web documents and give here a brief decription.

- The text (hypertext) starts from a Table of Contents and has main pages and others containing notes and more detailed information (comprising mathematical details) [3 , 4].
Figure 3 shows an example of four pages taken from the package. They include text, links, pictures and forms, as frequently found in a Web document.

- Inlined figures have been introduced to help users to understand the text using graphs, plots, histograms, etc.