  Even if Einstein's General Relativity achieved a great success and overcame
lots of experimental tests, it also showed some shortcomings and flaws which
today advise theorists to ask if it is the definitive theory of gravity. In
this letter Proceeding we show that, by assuming that advanced projects on the
detection of Gravitational Waves (GWs) will improve their sensitivity, allowing
to perform a GWs astronomy, accurate angular and frequency dependent response
functions of interferometers for GWs arising from various Theories of Gravity,
i.e. General Relativity and Extended Theories of Gravity, could aim in
discriminating among various theories.
