Reference for Bava Batra 29:8

שמואל כתב ספרו והכתיב (שמואל א כח, ג) ושמואל מת דאסקיה גד החוזה ונתן הנביא

[You say that] Joshua wrote his book. But is it not written, And Joshua son of Nun the servant of the Lord died?<span class="x" onmousemove="('comment',' Josh. XXIV, 29. ');">¹³</span> — It was completed by Eleazar. But it is also written in it, And Eleazar the son of Aaron died?<span class="x" onmousemove="('comment',' Ibid. 33. ');">¹⁴</span>

Jastrow