Columbia subject headings:
Drawing, Italian--Private collections--Exhibitions.
Guercino, 1591-1666--Exhibitions.
Mahon, Denis--Art collections--Exhibitions.
Harvard subject headings:
Ashmolean Museum--Exhibitions.
Drawing, Italian--Private collections--Exhibitions.
Guercino, 1591-1666--Exhibitions.
Mahon, Denis--Art collections--Exhibitions.
Princeton subject headings:
Guercino, 1591-1666--Exhibitions.