Skip to Main Content


General chemistry and biochemistry subject guide.

Introduction to Source Types

Scientists consult a wide variety of sources when working on research project. At the beginning of a project, it is helpful to collect background resources that provide helpful contextual information. After gathering insights from background resources, move to JMU Libraries' databases to find scholarly, peer-reviewed resources. 

While databases do provide good scientific resources, they also provide materials such as magazine articles, trade journals, and conference proceedings, among other resource types. It is important to recognize that different literature types (magazines, journals, etc.) have different roles to play when conducting research. The graphic below outlines the different types of sources found in databases. 

Flow chart outlining resources found in databases.

Magazines and trade publications might be good resources for collecting background information, but scholarly, peer-reviewed articles will provide research findings that have been evaluated by other experts in the field. Choose sources that align with your project's goals 

Source Types

A good way to decide whether the resource is a good fit for your project or not is to evaluate the resource's intended audience. Authors write with a particular readership in mind, so choose sources that align with your project's goals. The graphic below outlines common source audiences. 

Science Magazine Example: National Geographic


Science magazine example with a photo of a National Geographic magazine cover 


Science Magazines are a type of secondary source, and science magazines can provide good background information when starting a project. You might not be able to cite the magazine in your final project, but use the content to gather ideas. 

Trade Journal Example: C& EN Global Enterprise 



Trade journals will predominantly provide secondary sources; however, some trade journals might provide short technical reports of an author's primary research findings. Evaluate each article on it's own terms to discern if it is a primary or secondary source. 

Scholarly, Peer-Reviewed Example: ACS Applied Engineering Materials 



Scholarly journals will provide a mix of primary and secondary sources. For example, a journal might contain several review articles, which are a secondary sources, and several original research articles, which are primary sources. Read carefully to discern whether you are consulting a primary or secondary source. 

Tertiary, Primary, & Secondary Literature

In addition to falling into one of the material type categories listed above (journal, book, etc.), scientific resources also fall into one of these three categories: tertiary, primary, or secondary literature. A majority projects will use a mix of these source types, while others will only rely on primary sources. Consult your project's guidelines for insights in choosing the best materials for your work. 

Tertiary Sources: Sources that index, compile, abstract, or outline other materials.  

  • Usually no author is credited 
  • Examples include dictionaries or encyclopedias, Wikipedia, guidebooks, manuals, and handbooks

Primary Sources: Primary sources report events as they originally occurred and convey original thinking, report new discoveries, or share new information. 

  • Direct Observation 
  • Author is the researcher who conducted the experiment
  • Findings are usually presented in a scholarly, peer-reviewed article or in a technical report. Some research findings are also provided in books. 

Secondary Sources: Sources that offer an analysis, evaluation, or restatement of primary sources. 

  • Does not provide primary observation; relies of second-hand reviews or remarks 
  • Author did not conduct the research; rather, the author provides a summary of findings from other researchers. 
  • Secondary sources include review articles, literature reviews, some books, and science magazines, among others.