Found in 1 comment on Hacker News
dzlobin · 2010-10-15 · Original thread
Since Derek Sivers gave it to me and I've read through it, I think it'd be cool to pass it forth.

Citizen Marketers http://www.amazon.com/Citizen-Marketers-When-People-Message/...

It's not CS but it's an interesting read for those interested in product evangelism

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