Kalthoff, K. (2001). Analysis of biological development (2nd ed.). McGraw-Hill.
Chicago-viite (17. p.)Kalthoff, Klaus. Analysis of Biological Development. 2nd ed. Boston: McGraw-Hill, 2001.
MLA-viite (9. p.)Kalthoff, Klaus. Analysis of Biological Development. 2nd ed. McGraw-Hill, 2001.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.