https://www.cambridge.org/us/universitypress/subjects/computer-science/computing-general-interest/calendrical-calculations-ultimate-edition-4th-edition#resource

https://www.cambridge.org/us/universitypress/subjects/computer-science/computing-general-interest/calendrical-calculations-ultimate-edition-4th-edition#resources https://www.cambridge.org/us/universitypress/subjects/comput... The source code is available there.