Subject encyclopedias are a type of tertiary source and are excellent starting points for your research into a specific scientific controversy. As you read through articles, look for the answers to these questions:

• Who are the main people involved? With what institutions, if any, are they affiliated?
   
• When did this controversy take place?  When did it start?  When did it end? What else was going on in the world?

Once you've established the basic outline of your chosen scientific controversy, evaluate it in terms of its feasibility for your research project.  Key questions to answer include:

• What primary sources are available?  (If the original sources are not in English, can you find reliable translations?  If the primary sources were originally unpublished, do you have access to a scholarly, annotated edition of them?  Or if the original documents are currently housed in a distant archive or library, are digital copies available?)
   
• What scholarly literature exists on this topic?  In other words, what has the scholarly conversation been on this topic?

The Gale Virtual Reference Library is a platform for searching through and accessing hundreds of specific subject encyclopedia titles.

You also have the option of searching individual titles within the GVRL,  such as The Complete Dictionary of Scientific Biography.