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Saumarapitha is one of the four Kamarupa Pithas, the geographical divisions of ancient Kamarupa.
Boundaries
Sources defines boundaries of Saumarapitha as area between from the Bhairavi and the Dikarai river.
Journal of the Assam Research Society - Volumes 13-15 - Page 90,1959 Yoginl-tantra divides Kamarupa into four pithas or region (Ratna pitha, Swarna pitha, Kama pitha, and Saumara pitha)
Sen, Dineschandra (1988), The Ballads of Bengal - Volume 1, Mittal Publications, p. 375
Kakati, Banikanta (1967), The mother goddess Kamakhya, p. 7