Although I agree in concept with the "free" PDF, the book is part of the BBU serices and doing so would deny the authors of their royalties. Slaughter & Delwiche have done an excellent job and deserve their royalties.
Under the SAS Academic Program, SAS will provide pdf's of the course notes and a PowerPoint slide set, as well as a substantial price discount on the notes. I've used all in my course at various times. Because my teaching has been done in concert with a biostatistics class, the order of presentation is vastly different from either the SAS course notes or "the little sas book" so I've not been able to rely totally on either.
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