Scribd’s ebook subscription service (and its two main competitors Oyster and Kindle Unlimited) provide all titles to all users at all times. In other words, you never have to wait for an ebook to be returned.
You can read the complete Scribd blog post that includes a few examples of the Harcourt titles now available here.
Scribd editors also have selected 20 titles from Houghton Mifflin Harcourt in this new handpicked collection.