1. T. Asada andK. Takano,Attenuation of short period P waves in the mantle, J. Physics of the Earth11 (1963), 25.
2. A. Ben-Menahem, S. W. Smith andT.-L. Teng,A procedure for source studies from spectrums of long-period seismic body waves, Bull. Seism. Soc. Am.55 (1965), 203.
3. R. B. Blackman andJ. W. Tukey,The Measurement of Power Spectra (Dover 1959), 180 pp. Vol. 63, 1966/I)
4. L. M. Brekhovskikh,Waves in Layered Media (Academic Press 1960), 561 pp.
5. M. B�th,An investigation of the Uppsala microseisms, Thesis (Uppsala 1949), 168 pp.