In [a recent New Yorker] is a letter to the editor from Valerie Lawson, in response to Caitlin Flanagan's December 19 article on Pamela Travers, the creator of Mary Poppins. Lawson is the author of a biography of Travers, and her letter reads like a relatively benign effort to make clear the decades-long effort by Poppins scholars to tease out Travers's elusive life story. It did not begin that way, as this lengthy - and not so benign - e-mail thread between Lawson and editors at The New Yorker shows. The exchange offers a glimpse at the sausage-factory aspect of how the magazine handles complaints, and raises interesting questions about what journalists owe, in terms of recognition, to their sources.

Read on here at the Columbia Journalism Review.