Enoch - And the leaders of the heads of the thousands, who are placed over the whole creation and over all the stars, have also to do with the four intercalary days, being inseparable from their office, according to the reckoning of the year, and these render service on the four days which are not reckoned in the reckoning of the year.

Notes

The book of Enoch is not part of the canonical scriptures (The Bible) we know today and we don't know how accurate it is.

Some belive while Enoch is not inspired by God that it still serves as a historical book on the time before the flood. It's also quoted in the New Testament in Jude 1:14-15.

Because of this I wanted to include this book for historical reasons.

I would recommend reading the Bible first and foremost as it should be your foundation. Then if you are intrested you can take a look at the book of Enoch.