"Primary sources . . . are defined as the direct evidence of a time and place that you are studying – any material (documents, objects, etc.) that was produced by eyewitnesses to or participants in an event or historical moment under investigation. Secondary sources, in contrast, are interpretations – often generated by scholars – that are based upon the examination of multiple primary sources." (from Primary Source.org)
What types of primary sources might have been produced that would be relevant to your topic? Which persons or organizations might have produced materials?
Possible formats include:
Here is Colorado Mountain College's video about primary versus secondary sources of information in the sciences.