Extract the answer to the question from the following context. Question: Which of the following is not a means of promoting Lee's book: warnings, the Book of the Month Club, or release by Reader's Digest Condensed Books? Context: Despite her editors' warnings that the book might not sell well, it quickly became a sensation, bringing acclaim to Lee in literary circles, in her hometown of Monroeville, and throughout Alabama. The book went through numerous subsequent printings and became widely available through its inclusion in the Book of the Month Club and editions released by Reader's Digest Condensed Books.
warnings