The flag of <a href="https://en.wikipedia.org/wiki/Bulungan_Sultanate" class="extiw" title="en:Bulungan Sultanate">Bulungan Sultanate</a>, a classical state in indonesia.
<a href="https://id.wikipedia.org/wiki/User:Baskoro_Aji" class="extiw" title="id:User:Baskoro Aji">Baskoro Aji</a>
<span class="int-own-work" lang="">Own work by the original uploader</span>