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**Lecture 7**  ##  Externalities this is one referenced link:  https://www.cengagebrain.com.au/content/borland34288_0170134288_01.01_toc.pdf 
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here is a link that Google suggests is an option for actioning access to content:  http://www.gumtree.com.au/s-melbourne/principles+microeconomics/k0l3001317