Penso tu ti riferisca a questo:
Castellaro, S., and F. Mulargia (2009), VS30 Estimates Using Constrained H/V Measurements, Bulletin of the Seismological Society of America, 99(2A), 761-773.
Link:
http://www.bssaonline.org/cgi/content/abstract/99/2A/761

Esistono, sempre degli stessi Autori e stesso anno anche:
Castellaro, S., and F. Mulargia (2009), Estimates of Vs30 Based on Constrained H/V Ratio Measurements Alone, in Increasing Seismic Safety by Combining Engineering Technologies and Seismological Data, edited by M. Mucciarelli, et al., pp. 85-97. (http://www.springerlink.com/content/lgm35674h48kr4m1/)

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Castellaro, S., and F. Mulargia (2009), The Effect of Velocity Inversions on H/V, Pure and Applied Geophysics, 166(4), 567-592. (http://dx.doi.org/10.1007/s00024-009-0474-5 )