• DN is presented by a short Manual (which concerns FN, too) yielded as a pdf-file. 
• The program DN was conceived as working in DOS, but it does work now in Windows XP.

The program is given with a sample file of formulae to be studied. The help menu gives a complete introduction.

DN was (and is still some years) used at Nantes by students of philosophy, degree "Licence", "mention Logic".