GOST 8.420-1981 State system for ensuring the uniformity of measurements. State special standard and state verification schedule for means of measuring straightness and flatness deviation
2002GOST 8.420-2002 State system for ensuring the uniformity of measurements. State verification schedule for means of measuring straightness and flatness deviation
1981GOST 8.420-1981 State system for ensuring the uniformity of measurements. State special standard and state verification schedule for means of measuring straightness and flatness deviation