How many sources do I actually need? I'm drowning in PDFs 📄

[Eva]

I have 40 PDFs saved. FORTY. And I keep finding more. My professor said "you can never have too many sources" but at this point, I have too many to actually USE. I'm spending all my time reading and no time writing.

The Innovatank guide says research should be "focused and purposeful" — you need to know what you're looking for before you start drowning in articles .

For a 10-12 page paper, I'm hearing different numbers:

• Some say 8-10 good sources is plenty
• Others say 15-20 minimum for upper-level work
• My professor just says "enough to support your argument" (thanks, super helpful)

The University of Nottingham has a guide that suggests starting with your course readings and working backward — check their bibliographies to find key texts . That way you're not just randomly searching databases.

Another approach I found is the "3-2-1 method" :

• Find 3 recent articles on your topic
• Check their references for 2 key sources they all cite
• Find 1 scholar who seems central to the conversation
• Then search for THAT scholar's work and who's cited them

This is actually helping me narrow things down. Instead of 40 random articles, I now have maybe 12-15 really important ones.

The Qianbi AI tool claims to help with this — you upload your sources and it "generates literature reviews" and "identifies relationships between papers" . Has anyone used something like this? Does it actually help or just make more work?

For students who've written research papers: how do you decide which sources are actually essential? How do you know when you've done enough research and it's time to START WRITING? I'm scared of starting too early and missing something important, but also scared of never starting at all.