एपीए उद्धरण

S Vere Benson. Observer's book of Birds. Frederick marne and Co.

शिकागो स्टाइल उद्धरण

S Vere Benson. Observer's Book of Birds. Frederick marne and Co.

एमएलए उद्धरण

S Vere Benson. Observer's Book of Birds. Frederick marne and Co.