In Russian. Ageev, Leonid Efimovich. Basics of calculation of optimal and permissible modes of operation of machine and tractor units. Leningrad: Kolos. Leningrad Division, 1978 Osnovy rascheta optimalnykh i dopuskaemykh rezhimov raboty mashinno-traktornykh agregatov/Basis for calculating optimal and permissible modes of operation of machinery and tractor units In Russian. All images are for identification of editions only. Several books of the same edition may be available. Please feel free to request photos of available books. SKU7618795