This is referred to as an indirect source.
- Source A says, "The sky is blue."
- Source B says, "Source A says, 'The sky is blue.'"
- You want to say, "Source A, quoted in Source B, says 'The sky is blue.'"
In your citations you will give credit to both Source A (the originator of the information) and Source B (where you found the information).
The source in your hand (or on your screen) will be listed with citations at the end of your paper. The source that source quotes will be cited in a specific way, according to the citation style you are using, within the text of your paper.
For specific details on how to do this, visit the style guide for the citation style you are using (APA, MLA, etc), and look for "indirect source" in the menu of options.
You will find APA, MLA and other style guides on the library's Cite Your Sources page. There, within the style guide you select, you will find details on citing indirect sources in the menus for In-Text Citations.
