Columbia subject headings:
Genetic engineering--Congresses.
Insulin--Synthesis--Congresses.
Recombinant DNA--Congresses.
Somatotropin--Synthesis--Congresses.
Harvard subject headings:
Genetic engineering--Congresses.
Insulin--Synthesis--Congresses.
Recombinant DNA--Congresses
Somatotropin--Synthesis--Congresses.
Princeton subject headings: