(NmATERIALY K IZU^ENI@ RUSSKOGO GRAFITA (B:s 10 (NRIS(B. (NW TEKSTE (B/s - (NqHONTOW(B, (Nn(B.(Np(B.s; (NkOSTYLEWA(B, (Ne(B.s; (NlABUNCOW(B, (Na(B.s ((NlENINGRAD (B:s (Nb(B. (NI(B.,s, 1925)
Keywords: (NmINERALYs -- (NgRAFITs -- (NrOSSIQs