Mathematics
Mathematics
NOVIKOV, PYOTR SERGEYEVICH.
Elements of Mathematical Logic..Edinburgh & London, Olyver & Boyd, (1964).
VOLKOVYSKII, L.I.;LUNTS, G.L.;ARAMANOVICH, I.G.
A Collection of Problems on Co..New York, Dover Publ., 1991.
JEFFREYS, HAROLD and BERTHA SWIRLES.
Methods of Mathematical Physic..Cambridge, University Press, 1956.