Simpkins, J., & Williams, J. I. (1989). Advanced biology (3rd ed.). Unwin Hyman.
Cita Chicago (17th ed.)Simpkins, J., i J. I. Williams. Advanced Biology. 3rd ed. London: Unwin Hyman, 1989.
Cita MLA (8th ed.)Simpkins, J., i J. I. Williams. Advanced Biology. 3rd ed. Unwin Hyman, 1989.
Atenció: Aquestes cites poden no estar 100% correctes.