Garfinkel, Simson <br/><br/>
PGP: Pretty good privacy 
by Simson Garfinkel 
 - USA  O'Reilly & Associates  1995 
 - xxxiii, 393p. 
<br/><br/><label>ISBN: </label>1565920988 
<br/><br/><label>Dewey Class. No.: </label>005.82  / N951;1