Columbia subject headings:
Plastics--Biodegradation--Congresses.
Polymers--Biodegradation--Congresses.
Harvard subject headings:
Biodegradable plastics--Congresses.
Polymers--Biodegradation--Congresses
Princeton subject headings:
Plastics--Biodegradation--Congresses.
Polymers--Biodegradation--Congresses.