Gosler, A. (1987). Sexual dimorphism in the summer bill-length of the Great Tit. Nederlandse Ornithologische Unie.
Cita Chicago (17th ed.)Gosler, A. Sexual Dimorphism in the Summer Bill-length of the Great Tit. Nederlandse Ornithologische Unie, 1987.
Cita MLA (9th ed.)Gosler, A. Sexual Dimorphism in the Summer Bill-length of the Great Tit. Nederlandse Ornithologische Unie, 1987.
Atenció: Aquestes cites poden no estar 100% correctes.