- markup fix

- add clarifying words

Doc/ref/ref2.tex

@@ -652,7 +652,7 @@ Some examples of floating point literals:
 \end{verbatim}
 
 Note that numeric literals do not include a sign; a phrase like
-\code{-1} is actually an expression composed of the operator
+\code{-1} is actually an expression composed of the unary operator
 \code{-} and the literal \code{1}.
 
 

Doc/ref/ref6.tex

@@ -809,13 +809,14 @@ import __future__ [as name]
 That is not a future statement; it's an ordinary import statement with
 no special semantics or syntax restrictions.
 
-Code compiled by an exec statement or calls to the builtin functions
+Code compiled by an \keyword{exec} statement or calls to the builtin functions
 \function{compile()} and \function{execfile()} that occur in a module
 \module{M} containing a future statement will, by default, use the new 
 syntax or semantics associated with the future statement.  This can,
 starting with Python 2.2 be controlled by optional arguments to
-\function{compile()} --- see the documentation of that function in the 
-library reference for details.
+\function{compile()} --- see the documentation of that function in the
+\citetitle[../lib/built-in-funcs.html]{Python Library Reference} for
+details.
 
 A future statement typed at an interactive interpreter prompt will
 take effect for the rest of the interpreter session.  If an