They became so popular that in 2011, The New York Times introduced, or decided to publish, a separate list of popular e-books in addition to the paperback and hardback categories that it had always published.
它们变得如此受欢迎,以至于在 2011 年,纽约时报除了一直出版的平装和精装类别之外,还推出或决定出版一份单独的流行电子清单。