This whitepaper is for historical reference only. Some content might be outdated and some links might not be available.

# Document history
<a name="document-revisions"></a>

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| Change | Description | Date | 
| --- |--- |--- |
| [Whitepaper updated](#document-revisions) | Minor editorial changes made throughout. | July 13, 2023 | 
| [Whitepaper updated](#document-revisions) | Updated for technical accuracy. | September 15, 2021 | 
| [Initial publication](#document-revisions) | Whitepaper first published. | October 1, 2013 | 

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