Primary sources are the historical documents used by historians as evidence. Examples of primary sources include diaries, personal journals, government records, court records, property records, newspaper articles, military reports, military rosters, and many other things.
In contrast, a secondary source is the typical history book which may discuss a person, event or other historical topic. A good secondary source uses primary sources as evidence.
The key to determining whether an item may be considered to be a primary source is to ask how soon after the event was the information recorded. This can be a problem with an autobiography, memoir, reminiscence, etc. if the author is working several years with only the memory of what happened. Your history professor will disallow most or all of these as primary sources. However, the rule of thumb should always be: if you're not sure whether something is an acceptable primary source, ask your professor.
You may use these encyclopedias to find background information, dates, and possible other sources, but you cannot cite these in your paper.
In some of our databases, the database does not allow you to check that you are shown only peer-reviewed journal articles. To find out if a journal is refereed (also called peer-reviewed) you have two options:
1. Go to the journal publisher's web site to read the Advice to Authors and the About this journal. These are the most likely places that state if articles are sent out for peer-review.
2. Check Ulrichsweb (see below) to see if there is a little referee shirt icon in the left hand column. Search by journal name.