Vladimir Volovich writes:

 > Is it *stated* somewhere in documentation that one cannot use primitive TeX commands
 > (and syntax) in a LaTeX files? ;-)

No, but you were asking what are the correct LaTeX commands. See
Appendix E of the LaTeXbook.

 > > TeX has a syntax? New concept.... :-)
 >
 > Of course, it has. :-) If not, than how can one get LaTeX to have syntax?

By the very same argument, the ASCII code table has syntax, since you
can build Pascal, C, C++,... out of it. That's a red herring. TeX
input has a lexical structure that is determined dynamically during
the run, plus a macro language that doesn't have any syntax beyond the
notion of (token,catcode) pairs. Not even brace tokens are proper
syntactical elements, as the famous

  \ifnum0=`{\fi

example shows.

Over to Joachim Schrod.....

Rainer