Obligatory links to Lamport's "How to Write a Proof" [0], and "How to Write a 21st Century Proof."[1] A video presentation of the latter is discussed at [2].

[0] http://research.microsoft.com/en-us/um/people/lamport/pubs/l...

[1] http://research.microsoft.com/en-us/um/people/lamport/pubs/p...

[2] https://news.ycombinator.com/item?id=10689391

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