The concept behind the XFeature tool is described in this technical note . Familiarity with the tool concept, and hence with the content of the technical note, is essential for meaningful use of the tool itself.
The concept presented in the technical note is in turn based on the paper XML-Based Feature Modeling presented at the ICSR conference in 2004 and published in the book Software Reuse: Methods, Techniques, and Tools edited by J. Bosch and C. Krueger and published by Springer-Verlag.
The tool concept technical note is available as a PDF document. The reader for this document can be obtained for free at the Adobe Systems website.