Columbia subject headings:
Art, Roman--Italy--Sperlonga.
Sperlonga (Italy)--Antiquities.
Harvard subject headings:
Art, Roman--Italy--Sperlonga.
Grotto of Tiberius (Sperlonga, Italy)
Sperlonga (Italy)--Antiquities, Roman.
Sperlonga, Italy. Antro di Tiberio.
Princeton subject headings:
Art, Roman--Italy--Sperlonga.
Sperlonga (Italy)--Antiquities.