Columbia subject headings:
Agriculture--Bibliography--Study and teaching--Soviet Union.
Bibliography--Methodology--Study and teaching--Soviet Union.
Bibliography--Study and teaching--Soviet Union.
Natural history--Bibliography--Study and teaching--Soviet Union.
Technology--Bibliography--Study and teaching--Soviet Union.
Harvard subject headings:
Agriculture--Bibliography--Study and teaching--Soviet Union.
Bibliography--Methodology--Study and teaching--Soviet Union.
Bibliography--Study and teaching--Soviet Union.
Natural history--Bibliography--Study and teaching--Soviet Union.
Technology--Bibliography--Study and teaching--Soviet Union.
Princeton subject headings: