Thermal properties of the soil of Luna-20 and its terrestrial analogs Rzhevskii, V. V. ; Dukhovskoi, E. A. ; Kruglov, N. T. ; Petrochenkov, R. G. ; Silin, A. A. ; Shvarev, V. V. Abstract Publication: Soviet Physics Doklady Pub Date: April 1975 Bibcode: 1975SPhD...19..627R