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In his paper Niches, Slots, Grooves and Stains: Internal Frameworks in the Khufu Pyramid, Mark Lehner shows that wooden sections were originally installed in the sarcophagus chamber of Khufu. He notes the tradition of real or simulated wooden-frame and reed shrines within elite burial chambers dating back to the late Predynastic era. The reed mat shrine was symbolically inscribed and painted on the walls surrounding the sarcophagus inside the burial chamber of the pyramid of Unas.
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