Here
There was a discussion about the proper use of primes a while ago. You can find it here.
Thank you Chris and Nathan. That is what I believed to be the case, but before I sent off an e-mail to a rather prestigious design magazine, I wanted to check my facts.
We're in the process of moving, and I'm living in a sort of self-imposed hell because all my reference books are neatly packed away in storage, along with most of the rest of my office. 
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