<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">BibTeX seems to suffer from a Y2K-like bug. Here is an example:<div class=""><br class=""></div><div class="">====File bug.tex====</div><div class=""><br class=""></div><div class=""><div class="">\documentclass{article}</div><div class="">\begin{document}</div><div class=""><br class=""></div><div class="">BibTeX seems to suffer from a ``Y2K''-like bug --- it assigns the same key to references where the authous share the same first 3 characters in their last names, and the articles are published a multiple of 100 years apart.</div><div class=""><br class=""></div><div class="">This can be seen in~\cite{Smi19a}, \cite{Smi19b} and in~\cite{Smi19c}.</div><div class="">\thispagestyle{plain}</div><div class="">\bibliographystyle{alpha}</div><div class="">\bibliography{refs} {}</div><div class=""><br class=""></div><div class="">\end{document}</div><div class=""><br class=""></div><div class=""><br class=""></div></div><div class=""><br class=""></div><div class=""><div class="">====File refs.bib====</div></div><div class=""><br class=""></div><div class=""><div class=""><br class=""></div><div class="">@article{Smi19a,</div><div class="">  title={An article from 1819},</div><div class="">  author={Smith, John},</div><div class="">  journal={Ancient Journal},</div><div class="">  volume={1819},</div><div class="">  number={1},</div><div class="">  pages={12--13},</div><div class="">  year={1819}</div><div class="">}</div><div class=""><br class=""></div><div class="">@article{Smi19b,</div><div class="">  title={An article from 1919},</div><div class="">  author={Smither, Jonathan},</div><div class="">  journal={Old Journal},</div><div class="">  volume={1919},</div><div class="">  number={2},</div><div class="">  pages={112--113},</div><div class="">  year={1919},</div><div class="">  publisher={Springer}</div><div class="">}</div><div class=""><br class=""></div><div class="">@article{Smi19c,</div><div class=""><span class="Apple-tab-span" style="white-space:pre">   </span>Author = {Smithonian, Jane},</div><div class=""><span class="Apple-tab-span" style="white-space:pre">      </span>Journal = {New Journal},</div><div class=""><span class="Apple-tab-span" style="white-space:pre">  </span>Pages = {1--5},</div><div class=""><span class="Apple-tab-span" style="white-space:pre">   </span>Title = {An article from 2019},</div><div class=""><span class="Apple-tab-span" style="white-space:pre">   </span>Volume = {1},</div><div class=""><span class="Apple-tab-span" style="white-space:pre">     </span>Year = {2019}</div><div class="">}</div><div class=""><br class=""></div></div><div class=""><br class=""></div><div class="">==========</div><div class=""><br class=""></div><div class="">To reproduce the problem, save the files and run:</div><div class=""><br class=""></div><div class=""><div class="">  $  pdflatex bug</div><div class="">  $  bibtex bug</div><div class="">  $  pdflatex bug</div><div class="">  $  pdflatex bug</div></div><div class=""><br class=""></div><div class="">All 3 references in the pdf are labeled as <span style="font-family: CMR10; font-size: 10pt;" class="">[Smi19]</span></div>
                
        
        
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