Given the following passage  "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.",  answer the following question. Note that the answer is present within the text.  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?
warnings