function _determineCase($word)
    {
        $ret = -1;
        $trimmedword = trim($word);
        /*We need this variable. Without the next of would not work
         (trim changes the variable automatically to a string!)*/
        if (is_string($word) && (strlen($trimmedword) > 0)) {
            $i = 0;
            $found = false;
            $openbrace = 0;
            while (!$found && ($i <= strlen($word))) {
                $letter = substr($trimmedword, $i, 1);
                $ord = ord($letter);
                if ($ord == 123) { //Open brace
                    $openbrace++;
                }
                if ($ord == 125) { //Closing brace
                    $openbrace--;
                }
                if (($ord >= 65) && ($ord <= 90) && (0 == $openbrace)) { //The first character is uppercase
                    $ret = 1;
                    $found = true;
                } elseif (($ord >= 97) && ($ord <= 122) && (0 == $openbrace)) { //The first character is lowercase
                    $ret = 0;
                    $found = true;
                } else { //Not yet found
                    $i++;
                }
            }
        } else {
            throw new BibtexException('Could not determine case on word: ' . (string)$word);
        }
        return $ret;
    }