[1] 円柱座標変換 - Wikipedia (1/30/2017, 2:38:51 PM) <https://ja.wikipedia.org/wiki/%E5%86%86%E6%9F%B1%E5%BA%A7%E6%A8%99%E5%A4%89%E6%8F%9B>

[2] 極座標系 - Wikipedia (1/30/2017, 2:36:58 PM) <https://ja.wikipedia.org/wiki/%E6%A5%B5%E5%BA%A7%E6%A8%99%E7%B3%BB>