Columbia subject headings:
Algae, Fossil--Soviet Union.
Paleobotany--Carboniferous.
Paleobotany--Devonian.
Harvard subject headings:
Geology, Stratigraphic--Carboniferous
Geology, Stratigraphic--Devonian
Stromatolites--Russia (Federation)--Siberia.
Stromatolites--Russia (Federation)--Ural Mountains Region.
Princeton subject headings:
Algae, Fossil--Soviet Union.
Paleobotany--Carboniferous.
Paleobotany--Devonian.