APA-viite (7. p.)
Poulsen, E. (2009). Smiling bears: A zookeeper explores the behavior and emotional life of bears. Greystone Books.
Chicago-viite (17. p.)
Poulsen, Else. Smiling Bears: A Zookeeper Explores the Behavior and Emotional Life of Bears. Vancouver: Greystone Books, 2009.
MLA-viite (9. p.)
Poulsen, Else. Smiling Bears: A Zookeeper Explores the Behavior and Emotional Life of Bears. Greystone Books, 2009.
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