[3] WKB
[1] Well-known text - Wikipedia ( (7/2/2014, 3:24:18 AM 版)) http://ja.wikipedia.org/wiki/Well-known_text
[4] ジオメトリタイプ一覧をながめる (7/14/2018, 2:23:39 PM) https://qiita.com/yellow_73/items/6d1200b69b5d5c88bcd0
text/x-wkt
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