Columbia subject headings:
Harvard subject headings:
Interpersonal relations--Germany--History.
Love--Germany--Psychological aspects--History.
Marital status--Germany--Psychological aspects--History.
Marriage--Germany--Psychological aspects--History.
Princeton subject headings:
Interpersonal relations--Germany--History.
Love--Germany--Psychological aspects--History.
Marital status--Germany--Psychological aspects--History.
Marriage--Germany--Psychological aspects--History.