# Citation Management & Hallucination Prevention

This reference provides a complete workflow for managing citations programmatically, preventing AI-generated citation hallucinations, and maintaining clean bibliographies.

---

## Contents

- [Why Citation Verification Matters](#why-citation-verification-matters)
- [Citation APIs Overview](#citation-apis-overview)
- [Verified Citation Workflow](#verified-citation-workflow)
- [Python Implementation](#python-implementation)
- [BibTeX Management](#bibtex-management)
- [Common Citation Formats](#common-citation-formats)
- [Troubleshooting](#troubleshooting)

---

## Why Citation Verification Matters

### The Hallucination Problem

Research has documented significant issues with AI-generated citations:
- **~40% error rate** in AI-generated citations (Enago Academy research)
- NeurIPS 2025 found **100+ hallucinated citations** slipped through review
- Common errors include:
  - Fabricated paper titles with real author names
  - Wrong publication venues or years
  - Non-existent papers with plausible metadata
  - Incorrect DOIs or arXiv IDs

### Consequences

- Desk rejection at some venues
- Loss of credibility with reviewers
- Potential retraction if published
- Wasted time chasing non-existent sources

### Solution

**Never generate citations from memory—always verify programmatically.**

---

## Citation APIs Overview

### Primary APIs

| API | Coverage | Rate Limits | Best For |
|-----|----------|-------------|----------|
| **Semantic Scholar** | 214M papers | 1 RPS (free key) | ML/AI papers, citation graphs |
| **CrossRef** | 140M+ DOIs | Polite pool with mailto | DOI lookup, BibTeX retrieval |
| **arXiv** | Preprints | 3-second delays | ML preprints, PDF access |
| **OpenAlex** | 240M+ works | 100K/day, 10 RPS | Open alternative to MAG |

### API Selection Guide

```
Need ML paper search? → Semantic Scholar
Have DOI, need BibTeX? → CrossRef content negotiation
Looking for preprint? → arXiv API
Need open data, bulk access? → OpenAlex
```

### No Official Google Scholar API

Google Scholar has no official API. Scraping violates ToS. Use SerpApi ($75-275/month) only if Semantic Scholar coverage is insufficient.

---

## Verified Citation Workflow

### 5-Step Process

```
1. SEARCH → Query Semantic Scholar with specific keywords
     ↓
2. VERIFY → Confirm paper exists in 2+ sources
     ↓
3. RETRIEVE → Get BibTeX via DOI content negotiation
     ↓
4. VALIDATE → Confirm the claim appears in source
     ↓
5. ADD → Add verified entry to .bib file
```

### Step 1: Search

Use Semantic Scholar for ML/AI papers:

```python
from semanticscholar import SemanticScholar

sch = SemanticScholar()
results = sch.search_paper("transformer attention mechanism", limit=10)

for paper in results:
    print(f"Title: {paper.title}")
    print(f"Year: {paper.year}")
    print(f"DOI: {paper.externalIds.get('DOI', 'N/A')}")
    print(f"arXiv: {paper.externalIds.get('ArXiv', 'N/A')}")
    print(f"Citation count: {paper.citationCount}")
    print("---")
```

### Step 2: Verify Existence

Confirm paper exists in at least two sources:

```python
import requests

def verify_paper(doi=None, arxiv_id=None, title=None):
    """Verify paper exists in multiple sources."""
    sources_found = []

    # Check Semantic Scholar
    sch = SemanticScholar()
    if doi:
        paper = sch.get_paper(f"DOI:{doi}")
        if paper:
            sources_found.append("Semantic Scholar")

    # Check CrossRef (via DOI)
    if doi:
        resp = requests.get(f"https://api.crossref.org/works/{doi}")
        if resp.status_code == 200:
            sources_found.append("CrossRef")

    # Check arXiv
    if arxiv_id:
        resp = requests.get(
            f"http://export.arxiv.org/api/query?id_list={arxiv_id}"
        )
        if "<entry>" in resp.text:
            sources_found.append("arXiv")

    return len(sources_found) >= 2, sources_found
```

### Step 3: Retrieve BibTeX

Use DOI content negotiation for guaranteed accuracy:

```python
import requests

def doi_to_bibtex(doi: str) -> str:
    """Get verified BibTeX from DOI via CrossRef content negotiation."""
    response = requests.get(
        f"https://doi.org/{doi}",
        headers={"Accept": "application/x-bibtex"},
        allow_redirects=True
    )
    response.raise_for_status()
    return response.text

# Example: "Attention Is All You Need"
bibtex = doi_to_bibtex("10.48550/arXiv.1706.03762")
print(bibtex)
```

### Step 4: Validate Claims

Before citing a paper for a specific claim, verify the claim exists:

```python
def get_paper_abstract(doi):
    """Get abstract to verify claims."""
    sch = SemanticScholar()
    paper = sch.get_paper(f"DOI:{doi}")
    return paper.abstract if paper else None

# Verify claim appears in abstract
abstract = get_paper_abstract("10.48550/arXiv.1706.03762")
claim = "attention mechanism"
if claim.lower() in abstract.lower():
    print("Claim appears in paper")
```

### Step 5: Add to Bibliography

Add verified entry to your .bib file with consistent key format:

```python
def generate_citation_key(bibtex: str) -> str:
    """Generate consistent citation key: author_year_firstword."""
    import re

    # Extract author
    author_match = re.search(r'author\s*=\s*\{([^}]+)\}', bibtex, re.I)
    if author_match:
        first_author = author_match.group(1).split(',')[0].split()[-1]
    else:
        first_author = "unknown"

    # Extract year
    year_match = re.search(r'year\s*=\s*\{?(\d{4})\}?', bibtex, re.I)
    year = year_match.group(1) if year_match else "0000"

    # Extract title first word
    title_match = re.search(r'title\s*=\s*\{([^}]+)\}', bibtex, re.I)
    if title_match:
        first_word = title_match.group(1).split()[0].lower()
        first_word = re.sub(r'[^a-z]', '', first_word)
    else:
        first_word = "paper"

    return f"{first_author.lower()}_{year}_{first_word}"
```

---

## Python Implementation

### Complete Citation Manager Class

{% raw %}
```python
"""
Citation Manager - Verified citation workflow for ML papers.
"""

import requests
import time
from typing import Opt