Use reference sources for factual information like the date the Defense of Marriage Act was signed into law, or where in the United States Statutes at Large to find it. You can also use them to find more complex information, like marriage law in Islam. They often include bibliographies, making them profitable places to begin a research project.
Encyclopedias attempt to summarize the state of knowledge in a field of inquiry. A good encyclopedia can be a valuable starting point for your research.
There are many encyclopedias that compile knowledge about a specific nation or region. For example, Encyclopedia of Latin American History and Culture, Encyclopaedia Iranica, or Encyclopedia of the Third Reich. These encyclopedias will often include entries on marriage, divorce, and the family--they make excellent places to begin exploring possible topics. We've included a few of the more substantial titles in the list below.