1. M. Brovelli, F. Migliaccio (1993): “The direct estimation of the potential coefficients by biorthogonal sequences”. Lectures Notes in Earth Sciences (Sanso and Rummel eds.). Satellite Altimetry in Geodesy and Oceanography. Vol.50, pp. 421–441. Springer-Verlag Berlin Heidelberg.
2. M. Brovelli, F. Sansó (1990): “Gradiometry: the study of the Vyy component in the BVP approach”. Manuscripta Geodaetica n. 15, pp. 240–248.
3. ESA-NASA (1993): “STEP: Report on the phase A study”, SCI(93)4.
4. F. Migliaccio (1993): “Il progetto STEP: l’utilizzo geodetico”. Atti del 12° Convegno GNGTS. Roma.
5. F. Migliaccio, F. Sacerdote, F. Sanso (1989): “The boundary value problem approach to the data reduction for a spaceborne gradiometer mission”. General Meeting IAG, Edinburg, Aug. 3–12.