- 1
-  Type lexeme is
defined on page ??
- 2
-  Note of translators: From an
academic standpoint, the proper term 
would have been ``Rational Expressions''; we chose the
term ``regular'' to follow the programmers' tradition.
- 3
-  By convention, the empty word is denoted
by the greek character epsilon: e
- 4
-  We underline the portion of input processed at each 
stage and we point out the rule used.