I do have the book, so I'll look it up for you. It cites one paper by Grimm:
C. A. Grimm, A conjecture on consecutive composite numbers,
Amer. Math. Monthly,
76(1969) 1126-1128.
I imagine this is the original source, given the name, so I think the answer to your question is 1969 or thereabouts.
Edit: Here's a paper mentioning it:
http://www.math.tifr.res.in/~shanta/grimm.pdf
Here's a capsule review (typed, not printed!):
http://www.emis.de/cgi-bin/Zarchive?an=0197.32001
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