Found in 1 comment on Hacker News
VLM · 2016-06-20 · Original thread
Gray market would be a ... gray area.

This took some work to find, but I found it:

https://www.amazon.com/gp/product/B00HT4BF4U

Its a control theory textbook for $44 from a 3rd party. Which is a pretty good deal because the "real" book sitting on my desk is somewhat more expensive.

https://www.amazon.com/Modern-Control-Systems-13th-Richard/d...

In very tiny letters the cover of the cheap version reads "Circulation of this edition outside the Indian Subcontinent is Unauthorized"

Something I find hilarious is the grey market edition is full of reviews that boil down to "this textbook sux and I hate my prof" but the genuine edition has one review by one guy who probably doesn't exist because if you click thru his reviews all look like stereotypical three word filler material.

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