Great Soviet encyclopedia,Vol.3
Prokhorov,A M.
Great Soviet encyclopedia,Vol.3 - 3rd ed. - Newyork Macmillan 1973 - 781p.
037 / PRO/G.3
Great Soviet encyclopedia,Vol.3 - 3rd ed. - Newyork Macmillan 1973 - 781p.
037 / PRO/G.3