# Ebook & Academic Paper Resources

## Public Domain & Open Access Ebooks
- Project Gutenberg (gutenberg.org — 70,000+ free ebooks)
- Internet Archive (archive.org — millions of scanned books)
- Open Library (openlibrary.org)
- Standard Ebooks (standardebooks.org — carefully formatted public domain works)
- ManyBooks (manybooks.net)

## Academic Papers (Open Access)
- arXiv (arxiv.org — physics, math, CS, quantitative biology, etc.)
- PubMed Central (ncbi.nlm.nih.gov/pmc)
- DOIs via doi.org (resolves to publisher page; open access where available)
- Google Scholar (scholar.google.com — discovery; check for open access links)
- Semantic Scholar (semanticscholar.org)
- CORE (core.ac.uk — aggregator of open access repositories)
- Directory of Open Access Journals (doaj.org)

## Chinese Academic Resources
- CNKI / 知网 (user's institutional access)
- 万方 (user's institutional access)
- 维普 (user's institutional access)

## Tools
- curl -L -O URL (direct PDF downloads)
- wget -r (recursive download from open repositories)
- DOI resolution: `https://doi.org/DOI` → follow redirect to publisher page
