lunar-javascript: Copyright (c) 2018 6tail. MIT License. Full license: lunar-javascript-MIT.txt
Author: https://6tail.cn/calendar/lunar.yiji.html
Calendar and solar-term source: Hong Kong Observatory and DATA.GOV.HK. Rights remain with their original owners; this website is not their official service.
https://www.hko.gov.hk/tc/gts/time/24solarterms.htm