The principal Upaniṣads can be considered Vedic literature since they are included within the Brahmanas and Aranyakas.Patrick Olivelle (2014), The Early Upanishads, Oxford University Press, , pages 12-14.Bronkhorst, Johannes (2007). Greater Magadha: Studies in the Culture of Early India, pp. 258-259. BRILL. However, numerous scriptures titled "Upaniṣads" continued to be composed after the closure of the Vedas proper. Of these later "Upaniṣads" there are two categories of texts:Olivelle, Patrick (1992). The Samnyasa Upanisads, pp. 5, 8–9.. Oxford University Press. .Varghese, Alexander P. (2008), India : History, Religion, Vision And Contribution To The World, vol. 1, p. 101. Atlantic Publishers & Distributors,
