Herbert Weir Smyth, A Greek Grammar for Colleges

εἰ ἔστιν, ἣν σὺ πρότερον ἔλεγες ἀρετήν, ἀληθής (for ἔστιν ἡ ἀρετὴ ἀληθής, ἣν) if the virtue which you were speaking of before, is real P. G. 503c, εἰς δὲ ἣν ἀφί_κοντο κώμην μεγάλη ἦν (for ἡ κώμη εἰς ἣν) the village at which they arrived was large X. A. 4.4.2, κλῦθί μευ, δ̀ χθιζὸς θεὸς ἤλυθες (for θεὸς δ̀ or ὦ θεός) hear me thou that camest yesterday in thy godhead β 262.

a. An accusative antecedent is incorporated in the accusative when the verb of the relative clause takes the accusative. Thus, οὐκ ἀπεκρύπτετο ἣν εἶχε γνώμην (for τὴν γνώμην ἣν) he did not conceal the opinion he had X. M. 4.4.1, μηδ᾽ . . . ἀφέλησθε ὑ_μῶν αὐτῶν ἣν διὰ παντὸς ἀεὶ τοῦ χρόνου δόξαν κέκτησθε καλήν (for τὴν καλὴν δόξαν ἣν) do not deprive yourselves of the fair fame which you have enjoyed throughout all time D. 20.142.

b. An accusative antecedent may be incorporated as nominative, genitive, or dative, e.g. εἴ τινα ὁρῴη . . . κατασκευάζοντα ἧς ἄρχοι χώρα_ς (for τὴν χώρα_ν ἧς ἄρχοι) if ever he saw any one improving the district which he governed X. A. 1.9.19.