Rat Cave on Eua Island (Tonga), photo from book  Pinchuk V. V. "Two months of wanderings and 14 days of unfreedom", <a href="//commons.wikimedia.org/wiki/Special:BookSources/978-5-9909912-5-5" title="Special:BookSources/978-5-9909912-5-5">ISBN 978-5-9909912-5-5</a>.
<a href="//commons.wikimedia.org/wiki/User:%D0%92%D0%B8%D0%BA%D1%82%D0%BE%D1%80_%D0%9F%D0%B8%D0%BD%D1%87%D1%83%D0%BA" title="User:Виктор Пинчук">Виктор Пинчук</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>