めっちゃ強そう！引用・参考資料等 https://www.deepstorm.ru/DeepStorm.files/45-92/nts/945/list.htmhttps://www.deepstorm.ru/DeepStorm.files/45-92/nts/971/list.htmhttps://www.quora.com/Did-the-Soviet-Union-build-titanium-submarines-If-so-what-are-the-advantages-of-titanium-subs
http://www.nicovideo.jp/watch/sm43827410
