In the Cambridge Dictionary of Bibliography, Dickens accounts for twenty pages. Among those who have written books about him or studies of him are: Walter Bagehot, G. K. Chesterton, George Gissing, Frederic Harrison, Bret Harte, Arthur Machen, Sir Arthur Quiller-Couch, George Santayana, George Saintsbury, A. C. Swinburne, Anthony Trollope. Of Dickens, Mr. Bernard Shaw has remarked: 'So much is known about him that might have happened to Wickens or Pickens or Stickens that his biographers have obliterated him.' For those who wish to delve into sources, John Forster's Life (published in 1872-4) will provide the best starting point -- though it suppresses many details of Dickens's private affairs and is biased in its judgments on his friends. Several collections of Dickens's Letters have been published, the most complete of which is included in the Nonesuch Edition of his works published in 1938.