When you have a comprehensive list of potential sources of information you must evaluate these sources and decide which will provide the best information.
You must first determine whether a source is RELEVANT and then if it is RELIABLE.
Recent secondary sources are important because they provide new interpretations, introduce new evidence, and/or re-evaluate traditional sources or interpretations. However, some sources written in the past are seminal works or mark a watershed in the academic debate. Check the bibliographies of recent works for references to previous studies. These references may lead you to an important source of information.
The best sources usually have been published by a major university press or in a scholarly journal. You can also be confident that the source is important if it has been reprinted.
Size often indicates detail. A book or article that covers a long time span or broad subject in a short amount of space is too general to be used as a source of information in your paper.
The source should look and sound professional. Use your instincts: informal language, large print and lots of pictures do not belong in scholarly works.
Find out if the author has written about this subject before. Conduct an author search of your library's on-line catalog and of periodical indexes. If you find that he/she has written a number of articles or books on the topic, you can be relatively assured that the author is an expert in the field.
If you are still unsure of the value of a source, a book review can be very helpful. Book reviews are professional evaluations of the usefulness and significance of a source. Use this information to make your own judgement about the reliability of the source.
Use this information to compile a working bibliography of reliable and relevant sources. Once you have a working bibliography you are ready to begin reading intensively.
[Dartmouth University's "Six Reading Myths"]