Printing types. Type family 'Ladoga' (for alphabets of Russian and roman graphic bases). Range of application. Design. Base line. Characters per 4 picas
Explosive atmospheres. Part 37. Non-electrical equipment for explosive atmospheres. Non electrical type of protection constructional safety 'c', control of ignition source 'b', liquid immersion 'k'
State system for ensuring the uniformity of measurements. State primary standard and state verification schedule for means measuring electrical resistance
