1. P. Astone et al., Il Nuovo Cimento, 20C, No.1, 9 (1994).
2. P. Astone et al., Class. Quantum Grav., 19, 5449 (2002).
3. O. I. Shelukhin, Nongaussian Processes in Electronics [in Russian], Radio i Svyaz', Moscow (1999).
4. Yu. G. Sosulin, Theoretical Principles of Radar and Radio Navigation [in Russian], Radio i Svyaz', Moscow (1992).
5. P. Bonifazi et al., Astronom. and Astrophys. Trans., 22, 557 (2003).