Columbia subject headings:
Agriculture--Safety regulations--Russia (Federation)
Agriculture--Safety regulations--Soviet Union.
Collective farms--Law and legislation--Russia (Federation)
Collective farms--Law and legislation--Soviet Union.
Harvard subject headings:
Agriculture--Safety regulations--Soviet Union.
Collective farms--Law and legislation--Soviet Union.
Princeton subject headings:
Agriculture--Safety regulations--Soviet Union.
Collective farms--Law and legislation--Soviet Union.