ἃς παρέχειν sc. μαρτυροῦσι. For the infinitive in the relative clause influenced by the principal verb, cf. Or. 36 § 25.
εἶθ᾽ ἡ διαθήκη γέγραπται ‘Then follows a copy of the will,’ or (with Kennedy) ‘and then the will is set out.’ ‘Deinde sequitur (in testimonio eorum) testamentum exscriptum, sequitur exeniplum testamenti.’ Seager, Classical Journ. LX p. 267. Cf. Dem. 9 § 42 εἶθ᾽ ἡ αἰτία γέγραπται.