Columbia subject headings:
Harvard subject headings:
Birds--Asia--Identification.
Birds--Europe--Identification.
Passeriformes--Palearctic--Identification.
Passeriformes--Palearctic.
Princeton subject headings:
Birds--China--Identification.
Birds--Europe--Identification.
Birds--Former Soviet Republics--Identification.
Birds--Identification.
Birds--Japan--Identification.