Gray's Anatomy of the Human Body was first published in 1858 by Henry Gray. It's been built on ever since. Currently in its
40th edition, it's considered the authoritative sourcebook for pretty much all anatomical issues. Those who read it have less of a chance of
Failing Biology Forever—
if they don't go blind from eyestrain first.
The characters on the show
Grey's Anatomy might have read it during med school, but no one knows due to all the
screwing around going on there.
See also
Chekov's Gun.