Tertiary sources are generally not cited directly in academic writing. However, they can be useful as a jumping-off point when you begin the research process.
When you’re starting your research, you can use tertiary sources to:
Collect background information
Pick out keywords and terms
Learn current views on the topic
Identify key figures whose work may be useful to you
Tertiary sources can direct you to primary and secondary sources that you can use later during the writing process.