An apocryphal book mentioned in Joshua 10:13 and 2 Samuel 1:18. There are a number of translations, but since the original is lose to time, they cannot be verified.
(https://www.christianity.com/wiki/bible/what-is-the-book-of-jasher.html)
It holds accounts of significant moments in Israel's history.
(2 Samuel 1 (Part 2) Bible Study | Pastor Daniel Batarseh by Maranatha Bible Church - Chicago- https://www.youtube.com/watch?v=M80xL-pEIdk)
There is a book called “The Book of Jasher” today, although it is not the same book as mentioned in the Old Testament. It is an eighteenth-century forgery that alleges to be a translation of the “lost” Book of Jasher by Alcuin, an eighth-century English scholar. There is also a more recent book titled “The Book of Jashar” by science fiction and fantasy writer Benjamin Rosenbaum. This book is a complete work of fiction.
Another book by this same name, called by many “Pseudo-Jasher,” while written in Hebrew, is also not the “Book of Jasher” mentioned in Scripture. It is a book of Jewish legends from the creation to the conquest of Canaan under Joshua, but scholars hold that it did not exist before A.D. 1625. In addition, there are several other theological works by Jewish rabbis and scholars called “Sefer ha Yashar,” but none of these claim to be the original Book of Jasher.
(https://www.gotquestions.org/book-of-Jasher.html)
And David lamented with a lamentation over Saul and Jonathan his son called the Song of the Bow or the Lament of the Bow, and he said it should be taught to the people of Judah; behold, it is written in the Book of Jashar. (2 Samuel 1:18)