Columbia subject headings:
Sex (Psychology)
Sex customs--United States.
Sexual ethics.
United States--Moral conditions.
Harvard subject headings:
Erotica.
Hefner, Hugh M. (Hugh Marston), 1926-2017.
Playboy (Chicago, Ill.)
Sex (Psychology)
Sex customs--United States
Sex--Periodicals.
Sexual ethics.
United States--Moral conditions.
Princeton subject headings:
Sex (Psychology)
Sex customs--United States.
Sexual ethics.
United States--Moral conditions.