Sources :

S1. Great Pyramid Passages And Chambers by John and Morton Edgar Volume 1, London 1910.

S2. Great Pyramid Passages Vol. II  by John and Morton Edgar Volume 1, London 1913. 

S3. Ægyptens Pyramider (Original title: Pyramids of Egypt) by I.E.S. Edwards, translated by Erik Iversen, Copenhagen 1961.

S4. The Pyramid Builder´s Handbook by Derek K. Hitchins, UK 2010.

S5. The Pyramids and Temples of Gizeh, notes from excavations in 1880 to 1904  by Sir William Matthew Flinders Petrie (also called Flinders Petrie)Re-typed from the original book and printed in Memphis, USA, 2011.

S5orig  The Pyramids and Temples of Gizeh, a book with all the notes from the excavations in 1880 to 1904  by Sir William Matthew Flinders Petrie published by Field & Tuer in London in 1883. Reprinted on Demand by University Microfilms International, Ann Arbor, London. Required from Cornell University Library. (The same source as S5 but much more comprehensive).

S6. Charles Piazzi Smith,  (3 January 1819 – 21 February 1900) was an English astronomer.

S7.  https://en.wikipedia.org/wiki/Ancient_Egyptian_mathematics

S8. http://www.reshafim.org.il/ad/egypt/religion/body_and_soul.htm

S9. Handwritten notebooks  by Sir William Matthew Flinders Petrie as a courtesy of the Petrie Museum of Egyptian Archaeology, UCL

S10. Kunst & Arkitektur  Egypten by Matthias Seidel and Regine Schulz, 2006
S11. Pyramids of the Gia Plateau by Charles Rigano, 2015
S12. GIZA and the PYRAMIDS, the definitive story by Mark Lehner and Zahi Hawass, 2017
S13. The complete Pyramids, Solving the Ancient Mysteries by Mark Lehner, 1997.

S14.  http://www.drhawass.com/wp/ 

S15. "Niches, Slots, Grooves and Stains: Internal Framework in the Khufu Pyramid?" by Mark Lehner  published in  https://www.academia.edu/36645718/Niches_Slots_Grooves_and_Stains_Internal_Frameworks_in_the_Khufu_Pyramid  

S16. "Examining The Grand Gallery in The Pyramid of Khufu And its Features" by Luca Miatello in PalArch´s Journal of Achaeology of Egypt/Egyptology, 7(6) (2010)