Greenbook and Bluebook refer to which agency is accrediting hospitals for Clinical Rotations:
Greenbook - Accreditation Council for Graduate Medical Education (ACGME)
Bluebook - American Osteopathic Association (AOA)
The significance for med students is that certain states require a certain amount of or certain types of Rotations be completed in Greenbook Hospitals (ACGME accredited).
For Mass you should find the State licensing agency, look at their website and give them a call. They will be the best source of Mass licensing requirements.
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