References
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- Chai, A. (2017). Catching up with Bernard Harrison, Singapore’s very own zoo tycoon [SG Now]. Retrieved from http://sg.asia-city.com/people/news/bernard-harrison-singapore-zoo-tycoon
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- Mason, G. (2008). Stereotypic animal behaviour: Fundamentals and applications to welfare (2nd ed.). Wallingford, England: CABI.
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