Herbert Weir Smyth, A Greek Grammar for Colleges

““οἱ μὲν αὐτῶν, οἱ δ᾽ οὔ” some of them and not others” P. A. 24e, ““οἳ ὕστερον ἐλήφθησαν τῶν πολεμίων” those of the enemy who were taken later” X. A. 1.7.13, ““οὐδεὶς ἀνθρώπων” no one in the world” P. S. 220a, ““τὶ τοῦ τείχους” a part of the wall” T. 7.4, ““τὶς θεῶν” one of the gods” E. Hec. 164 (““τὶς θεός” a god” X. C. 5.2.12), ““ἓν τῶν πολλῶν” one of the many things” P. A. 17a; rarely after demonstrative pronouns: τούτοις τῶν ἀνθρώπων to these (of) men T. 1.71.

a. With ὀλίγοι and with numerals ἀπό and ἐξ are rarely added: ““ἐκ τριῶν ἕν” one of three” S. Tr. 734. ἐξ with superlatives is also rare. See also 1688. 1 c.