Kommentar zu Schemuel II 23:39

Thirty-seven. They are not [all] mentioned here²⁴Rashi seems to hold that only thirty-three of the thirty-seven are accounted for, the three first warriors, Adino, Elozor and Ahamoh. Then the thirty that are enumerated starting from verse 24 but not including Asoel, see the Metsudos Dovid on that verse. and I say Yoav did not have to be mentioned because he was the general [commanding] the army and the rest that are missing it is possible that they are three or four sons of Yeshai.²⁵Having accounted for thirty-three out of thirty-seven, four are missing. Rashi seems to be offering two distinct possible answers, either the four are Yoav and three of Yeshai’s sons or Yoav is not being counted here as part of the group of thirty-seven and the four missing are all sons of Yeshai.