Columbia subject headings:
Musicians--Correspondence.
Spiering, Theodore, 1871-1925--Correspondence.
Spiering, Theodore, 1871-1925.
Harvard subject headings:
Musicians--Correspondence
Spiering, Theodore, 1871-1925
Spiering, Theodore, 1871-1925--Correspondence.
Princeton subject headings:
Musicians--Correspondence.
Spiering, Theodore, 1871-1925--Correspondence.