2.取引又は証明における規制(METI/経済産業省) < https://www.meti.go.jp/policy/economy/hyojun/techno_infra/11_gaiyou_tani2.html >
“うるう秒”しばらくは存続、ITUの世界無線通信会議で決定 (2015年)
-INTERNET Watch Watch < https://internet.watch.impress.co.jp/docs/news/731707.html >
IERS - IERS Bulletins < https://www.iers.org/IERS/EN/Publications/Bulletins/bulletins.html >
NO leap second will be introduced at the end of December 2021.