Columbia subject headings:
Ear--Surgery--Methodology.
Nose--Surgery--Methodology.
Otolaryngology--Surgery--Methodology.
Surgical instruments and apparatus--Methodology.
Throat--Surgery--Methodology.
Harvard subject headings:
Ear--Surgery--Methods.
Nose--Surgery--Methods.
Otolaryngology--Surgery--Methods.
Surgical instruments and apparatus--Methods.
Throat--Surgery--Methods.
Princeton subject headings: