Columbia subject headings:
Life cycle, Human--Longitudinal studies.
Older people--Psychology.
Older people--United States--Psychology.
Harvard subject headings:
Life cycle, Human--Longitudinal studies.
Older people--Psychology.
Older people--United States--Psychology.
Princeton subject headings:
Life cycle, Human--Longitudinal studies.
Older people--Psychology.
Older people--United States--Psychology.