From the early Church Fathers to now.
“He said to them: Take with you the servants of your lord, and set my son Solomon upon my mule: and bring him to Gihon.”
“[David] orders [Zadok, Nathan and Benaiah] to make "Solomon ride [his] mule," because this animal was highly valued among the Hebrews, just like the white donkey among the Romans. The Jews, in fact, did not possess mules, since they were not allowed to "breed their animals with another kind," but mules were bought at very high prices from the Gentiles.”
“[David] orders them to bring [Solomon] down to Šiloha, where the tabernacle was, not far from the spring of water, which is called Šiloha. Šiloha is a Hebrew name, which is given because the water of the spring gushes out straight up and on and off; indeed, it does not gush out regularly and all the time. And the same can be said about the Nile: since, at different intervals, it suddenly becomes full and then overflows, it is called Gihon, because its waters spread out.”
The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.