Upanishads and Advaita are to each other what Christianity and New Testament are to each other. To exclude Advaita's reference from the lead of an article about Upanishads is like excluding the reference to Christianity in an article about New Testament. Advaita derives its authority from Upanishads which are part of Vedas. Adi Sankara and Ramanuja wrote the most notable exegeses on Upanishads. They are citable in the lead for just this reason alone. Thanks.   

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