1. GOST R 8.567-99, The State System of Measurements: Measurement of Time and Frequency: Terms and Definitions [in Russian].
2. GOST 8.381-80 (Comecon Standard 403-76), The State System of Measurements: Standards: Methods of Expressing Errors [in Russian].
3. RMG 29-99, The State System of Measurements: Metrology: Basic Terms and Definitions [in Russian].
4. Yu. F. Smirnov, Izmer. Tekh., No. 3, 42 (2007);
5. Measurement Techniques, 50, No. 3, 293 (2007).