Wanted to buy an ebook textbook available on #kindle, vitalsource, or redshelf. After deliberation, decided I need to be able to annotate, and narrowed choices down to #vitalsource vs #redshelf. After logging in and trying out some OER textbooks to see how annotating and the reader interfaces function, I chose #vitalSource. The reader interface was the deciding factor. #academicChatter
The implication of elsewhere on the #YaleUniversityPress site is that it doesn't actually distribute e-books itself but has an agreement with some company named #VitalSource as the favoured e-book distributor amongst several others.
https://yalebooks.yale.edu/ebook-information/
It looks like VitalSource has decided not to carry all YUP books. There were 2 more at the bottom of the page that were also out of print as e-books.