Tao-sheng Commentary on the Lotus Sutra, p168[T]he four great heavenly-kings
In the east of Sumeru is [the king] called Dhṛtarāṣṭra, in the south Virūḍhaka, in the west Virūpāksha, and in the north Vaiśravaṇa. They are controlled by Śakra-Devānām-Indra.