Columbia subject headings:
Cohort analysis.
Families--Europe.
Families--United States.
Life cycle, Human.
Social change.
Harvard subject headings:
Cohort analysis.
Families--Europe.
Families--United States.
Life cycle, Human.
Social change.
Princeton subject headings:
Cohort analysis.
Families--Europe.
Families--United States.
Life cycle, Human.
Social change.