Columbia subject headings:
Night work--Physiological aspects--Congresses.
Night work--Social aspects--Congresses.
Shift systems--Physiological aspects--Congresses.
Shift systems--Social aspects--Congresses.
Harvard subject headings:
Princeton subject headings:
Night work--Physiological aspects--Congresses.
Night work--Social aspects--Congresses.
Shift systems--Physiological aspects--Congresses.
Shift systems--Social aspects--Congresses.