2014GOST 13047.18-2014 Nickel. Cobalt. Methods for determination of arsenic
2002GOST 13047.18-2002 Nickel. Cobalt. Methods for determination of arsenic
1980GOST 741.9-1980 Cobalt. Method for the determination of arsenic
0000 GOST 741.9-1969
GOST 741.9-1980 Cobalt. Method for the determination of arsenic was changed to GOST 13047.18-2002 Nickel. Cobalt. Methods for determination of arsenic.