In addition to showcasing your knowledge of the graphic novel as a genre, this project requires you to demonstrate your abilities to research your historical/cultural/political moment or famous Hispanic person's life.
This guide provides links to resources as well as tips and tricks for finding more effective "free" resources.
Consider how different source types are going to give you different depths of information. Depending on your topic and focus, different resources will make more sense for you!
Not all relevant and effective resources are locked beyond paywalls. The open web can be useful to you, but you have to know how to search to your advantage.
Use the Google Advanced features to your advantage. The more precise and narrow your search, the more likely you can find something of use.
Perhaps limiting your search to a particular country will offer different perspectives.
For example, searching "Dirty War" in English on the global web will return very different results than searching "Guerra Sucia" and limiting it to Argentinian web addresses in Spanish.
While you are a student at UNI, you have access to Rod Library resources. There are other public organizations that exist to preserve cultural heritage, however. Consider searching by domain or even a particular website to find information on your topic.
For example, searching "Frida Kahlo" site:.si.edu will bring up anything the Smithsonian has digitally referenced for Frida Kahlo. Spoiler alert, there is some very cool stuff.