I hate to bring this up... but in the 3.0 unported licenses, 1(b), the definition of Collection, has a reference by section number to the definition of Work. Except in the [CC BY-SA 3.0 Unported] license, where the section number given 1(f), is to the definition of Licensor. I believe it should be 1(h), which is the the definition of Work in BY-SA 3.0 unported.
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From @dpoirier on Slack:
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