Influential Pulitzer Prize–winning American author (1878–1968) of such muckraking classics as The Jungle, Boston, and Oil!, the last of which served as the basis for the acclaimed 2007 film There Will Be Blood. TLS signed “Sinclair,” one page, 8.5 x 5.5, personal letterhead, March 17, 1932. Letter to writer and journalist Louis Adamic. In part: “I have been swamped with work and cares in connection with the Eisenstein Mexican picture. I enclose two copies of a letter which you may use anywhere that you wish. I have publishers in Prague…They will put you in touch with interesting people I am sure. In Austria you should meet Robert Wurmfeld…a very nice young chap, who introduced my son and his wife to many interesting people. My German publishers…will be glad to meet you and perhaps to publish your books.” Letter is affixed to a slightly larger black sheet. Three vertical folds, one through a single letter of signature, punch holes to left edge, and a bit of scattered light toning, otherwise fine condition. RRAuction COA.