Get BibTeX from Arxiv identifiert.

arxiv.php

<?
error_reporting(E_ALL);
/* use the arXiv API: http://arxiv.org/help/api/index */

function startsWith($haystack, $needle) {
    return $needle === "" || strpos($haystack, $needle) === 0;
}

function getLastname($name) {
    $tmp = explode(' ', $name);
    return end($tmp);
}

function file_get_contents_curl($url) {
    // http://stackoverflow.com/a/6595112/562769
    $ch = curl_init();

    curl_setopt($ch, CURLOPT_HEADER, 0);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); //Set curl to return the data instead of printing it to the browser.
    curl_setopt($ch, CURLOPT_URL, $url);

    $data = curl_exec($ch);
    curl_close($ch);

    return $data;
}

function printEntry($entry){
    $author = $entry->author->name;
    $title = trim(preg_replace('/\s\s+/', ' ', $entry->title));
    $datePublished = strtotime($entry->published);

    /* Try to find version. Assume version one in case of no hit. */
    $version = 1;
    preg_match("/[0-9]{4}\.[0-9]{4}v[0-9]+/", $entry->id, $matches);
    if (count($matches)==1) {
        $version = substr($entry->id, strlen("http://arxiv.org/abs/1207.0016v"));
    }

    /* Print everything*/
    ?>
<pre>
@Online{<?echo strtolower(getLastname($author));?>,
  author      = {<?
$i=0;
foreach($entry->{'author'} as $author ) {
    if ($i != 0) {
        echo " AND ";
    }
    echo $author->name;
    $i++;
}

?>},
  title       = {<?echo $title;?>},
  version     = {<?echo $version;?>},
  date        = {<?echo date('Y-m-d', $datePublished);?>},
  eprinttype  = {arxiv},
  eprintclass = {<?
$i=0;
foreach($entry->{'category'} as $cat ) {
    if ($i != 0) {
        echo ", ";
    }
    echo($cat["term"]);
    $i++;
}

?>},
  eprint      = {<?echo $entry->id;?>}
}
</pre>

    Link: <a href="<?echo $entry->id;?>"><?echo $entry->title;?></a>
    <?
}

/********************************************************************
 * Main                                                             *
 *******************************************************************/
if(isset($_GET['id'])) {
    $id = $_GET['id'];
    preg_match("/[0-9]{4}\.[0-9]{4}/", $id, $matches);
    if (count($matches)==1) {
        $id = $matches[0];
    }

    /* Get archive XML information about paper */
    $html = file_get_contents_curl("http://export.arxiv.org/api/query?search_query=".$id."&start=0&max_results=1");
    $xml = new SimpleXMLElement($html);
    $entries = $xml->entry;

    if ($entries != "") {
        foreach ($entries as $entry) {
            printEntry($entry);
        }
    } else {
        echo "arXiv did not find '".$id."'. ";
    }
} else {
    $id = "http://arxiv.org/abs/1112.4344";
}

?>

<hr/>

Please enter <a href="http://arxiv.org/">arXiv</a> id or full URL:
<form method="GET">
    <input type="text" name="id" id="id" value="<?echo $id;?>" style="width:80%"/>
    <input type="submit" />
</form>

<h2>More BibTex-Information</h2>
<ul>
  <li><a href="http://texblog.org/2007/08/09/how-to-use-a-bibtex-file/">How to use Bibtex as a reference library for Latex</a></li>
  <li><a href="http://www.bibtex.org/Using/de/">Wie benutzt man BibTeX mit LaTeX</a></li>
  <li><a href="http://manas.tungare.name/software/isbn-to-bibtex/">ISBN to BibTeX</a></li>
</ul>