Columbia subject headings:
Katz, Alex, 1927---Exhibitions.
Vallotton, Félix, 1865-1925--Exhibitions.
Harvard subject headings:
Katz, Alex, 1927---Exhibitions.
Vallotton, Félix, 1865-1925--Exhibitions.
Princeton subject headings:
Katz, Alex, 1927---Exhibitions.
Vallotton, Félix, 1865-1925--Exhibitions.