Tokyo Metro Chiyoda Line icon
Maxima m
Own work  using: <a class="external free" href="https://ja.wikipedia.org/wiki/%E7%94%BB%E5%83%8F:BSicon_TokyoChiyoda.svg">http://ja.wikipedia.org/wiki/%E7%94%BB%E5%83%8F:BSicon_TokyoChiyoda.svg</a>