ASCOLTANDO L'INFINITO SILENZIO: STORIA E LEGGENDA DEL PROGRAMMA SETI
(Emmeciquadro n. 13/2001, pp. 45-64)
ON THE LAST TERMS OF DRAKE EQUATION: THE PROBLEM OF ENERGY SOURCES AND THE “RARE EARTH HYPOTHESIS”
(Proceedings of the First European Workshop on Exo/Astrobiology, Frascati, 21-23 May 2001, ESA SP-496, August 2001, pp. 379-382)
