You must prove the major statements you make by citing sources that suggest you can do the things you are doing. Stone is one source. The direct marketing library has additional sources. You may use the web and internet sources, as well. Sources that prove you understand your target market and that your product line and catalog selections were based on information sources, instead of on guessing, are very important.
Many students overlook the importance of sources.
The sources you use justify the decisions you make. They also prove that you know what you are talking about. Your paper should have many different sources cited and they should be cited often. They should be about the target market, about the products, about how to do catalogs, about mailing lists and how to select them, etc. As a rough estimate, there should be two or three different sources cited per academic page written.