Books take much longer to write than articles and provide a broader look at a topic. Don't forget to include some books, either electronic or in paper, when you are starting your research.
When confronting a book on your topic, you will often not have time to read the entire document. Look at the title page, the table of contents, the preface and the introduction. These pages will give a lot of information about what is in the book. Then you can read the relevant chapters. To make sure you have found all the pages where your topic is discussed, look in the index for your topic.