bibliographies contain two main sections; the bibliographic information section and the annotations section. Since the formats may slightly vary from one institution to another and amongst scholars and researchers depending on the regulations, courses and materials being annotated, it is imperative to ask for specific guidelines. The bibliographic information There are also bibliography annotations that combine all three types (MLA, APA and Chicago style). When deciding on the style for an annotated bibliography, one should consider its purpose and the instructions given. Regardless of the formatting style required, all annotated bibliography pieces need to follow the same rule: the author's last name should be the only part that is flush left, while the rest of the text requires to be indented. The bibliographic information is written before the annotation using the suitable referencing style. The information is normally identified using a hanging indent. Generally, though, the bibliographic information of the source (the title, author, publisher, date, etc.) is written in either MLA or APA format. The annotations The annotations for each source are written in paragraph form. The lengths of the annotations can vary significantly from a couple of sentences to a couple of pages. The length of the annotation should be between 100 and 200 words. When writing summaries of sources, the annotations may not be very long. However, when writing an extensive analysis of each source, more space may be needed. A few sentences of general summary followed by several sentences of how the work fits into a larger paper or project that can be useful when writing a draft. Writing Sample entry of an APA style annotated bibliography: References External links Writing an annotated bibliography - University of New England How to Prepare an Annotated Bibliography - Cornell University Library Bibliography Book design