Papyrus of Ani, British Museum (New Kingdom), a Book of the Dead.
Key myth
Atum emerged from Nun on the primeval mound and made Shu and Tefnut from himself (the Pyramid Texts say he spat them out; the Memphite theology gives Ptah the same creative role through speech).
Where sources differ or caution applies. Atum was merged with the sun god as Ra-Atum, the setting sun.