re available in TEST_VALUES.
    </p>

    <h3 align = "center">
      Reference:
    </h3>

    <p>
      <ol>
        <li>
          Milton Abramowitz, Irene Stegun,<br>
          Handbook of Mathematical Functions,<br>
          National Bureau of Standards, 1964,<br>
          ISBN: 0-486-61272-4,<br>
          LC: QA47.A34.
        </li>
        <li>
          Robert Corless, Gaston Gonnet, David Hare, David Jeffrey, 
          Donald Knuth,<br>
          On the Lambert W Function,<br>
          Advanc