I do believe that professor needs to be brought up on ethics charges… do they do that?
Oh, yes. I had a computer science professor who required his own book each year. And because the field was rapidly progressing at the time, he brought out a new edition each year, so no used textbooks. And those books are very expensive, because of all the hand set diagrams.
I heard the professors get kickbacks from the publishers for switching books and or new editions every year. The books could be E-books which be cheaper than the hard copy.
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