Changes how creators are listed depending on their numbers

multiple_creators.php

<?php

/**
 * One Creator: "Jane Doe"
 * Two creators: "Jane Doe and John Doe"
 * Three creators: "Jane Doe, John Doe, and Jim Doe"
 * Four or more: "Jane Doe et al."
 */
    if ($creators) {

        $numCreators = count($creators);

        if ($numCreators > 3) {

          $cite .= $creators[0] . ' et al., ';

        } else {

          $separator = ' and ';

          if ($numCreators == 3) {
              $separator = ', and ';
          }
    
          $cite .= join($separator, array_filter(array_merge(array(join(', ', array_slice($creators, 0, -1))), array_slice($creators, -1)))) . ', ';
            
        }
    }