Columbia subject headings:
Herpes simplex virus--Congresses.
Mouth--Ulcers--Etiology--Congresses.
Mouth--Ulcers--Prevention--Congresses.
Harvard subject headings:
Herpes simplex virus--Congresses.
Herpes simplex--Congresses.
Mouth--Ulcers--Etiology--Congresses.
Mouth--Ulcers--Prevention--Congresses.
Princeton subject headings: