upanisadbhih
upaniṣadbhiḥ ca — and by studying the Vedic knowledge of the Upaniṣads; SB 10.8.45
upaniṣadbhiḥ — by the followers of the Upaniṣads, the most exalted portion of Vedic knowledge (as Brahman); CC Madhya 19.204
upaniṣadbhiḥ — by the followers of the Upaniṣads, the topmost portion of Vedic knowledge; CC Antya 7.33