Polakowski, K. J. (1987). Zoo design: The reality of wild illusions. University of Michigan, School of Natural Resources.
Chicago-viite (17. p.)Polakowski, Kenneth J. Zoo Design: The Reality of Wild Illusions. [Ann Harbor]: University of Michigan, School of Natural Resources, 1987.
MLA-viite (9. p.)Polakowski, Kenneth J. Zoo Design: The Reality of Wild Illusions. University of Michigan, School of Natural Resources, 1987.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.