The New Series Adventures are a series of novels relating to the long-running BBC science fiction television series, Doctor Who. The 'NSAs', as they are often referred to, are published by BBC Books, and are regularly published twice a year. Beginning with the Tenth Doctor, a series of 'Quick Reads' have also been available, published once a year. With exception to the Quick Reads, all of the NSAs have been published in hardcover to begin with, and have been reprinted in paperback for boxed collections that are exclusive to The Book People and Tesco. Some of the reprints amend pictures of the companion of the novel from the cover. Some of the hardback editions have also been reprinted to amend pictures of Rose. Source: Wikipedia (en)