Jaiminīya Upaniṣad Brāhmaṇa 2.2.9

2.2.9

atha vā ata ṛksāmnor eva prajātiḥ
sa yad dhiṅkaroty abhy eva tena krandati
atha yat prastauty aiva tena plavate
atha yad ādim ādatte reta eva tena siñcati
atha yad udgāyati reta eva tena siktaṃ sambhāvayati
atha yat pratiharati reta eva tena sambhūtam pravardhayati
atha yad upadravati reta eva tena pravṛddhaṃ vikaroti
atha yan nidhanam upaiti reta eva tena vikṛtam prajanayati
saiṣa rksāmnoḥ prajātiḥ /

Now then begins the procreation of ṛc and sāman:
When he utters the hiṅkāra, he roars toward [her] by that;
when he chants the prastāva, he leaps onto [her] by that;
when he takes up the ādi, he emits semen by that;
when he chants the udgītha, he causes the emitted semen to develop by that;
when he chants the pratihāra, he makes the developed semen grow by that;
when he chants the upadrava, he gives form to the grown semen by that;
when he reaches the nidhana, he brings forth the formed semen by that;
this is the procreation of ṛc and sāman.