Manava Dharmashastra 9.18

9.18

nāsti strīṇāṃ kriyā mantrair iti dharme vyavasthitiḥ
nirindriyā hy amantrāś ca 'nṛtam iti sthitiḥ //

For women no (sacramental) rite (is performed) with sacred texts, thus the law is settled; women (who are) destitute of strength and destitute of (the knowledge of) Vedic texts, (are as impure as) falsehood (itself), that is a fixed rule.