Muhammad's letters to the heads of state - sources analisys of the English Wikipedia aritle

al-islam.org

11. "The Events of the Seventh Year of Migration - The Message". www.al-islam.org. Al-Islam.org. Archived from the original on 5 August 2012. Retrieved 25 August 2013.

17. "the original of the letter was discovered in 1858 by Monsieur Etienne Barthelemy, member of a French expedition, in a monastery in Egypt and is now carefully preserved in Constantinople. Several photographs of the letter have since been published. The first one was published in the well-known Egyptian newspaper Al-Hilal in November 1904" Muhammad Zafrulla Khan, Muhammad: Seal of the Prophets, Routledge & Kegan Paul, London, 1980 (chapter 12). The drawing of the letter published in Al-Hilal was reproduced in David Samuel Margoliouth, Mohammed and the Rise of Islam, London (1905), p. 365, which is the source of this image.

1. Guillaume, Alfred (1967). The Life Of Muhammad: A Translation of Ishaq's Sirat Rasul Allah (13th ed.). Karachi: Oxford University Press. p. 653. ISBN 0-19-636033-1. Retrieved 18 August 2021.
3. Guillaume, A. (1955). Ibn Ishaq's Sirat Rasul Allah - The Life of Muhammad Translated by A. Guillaume. Oxford University Press.
17. "the original of the letter was discovered in 1858 by Monsieur Etienne Barthelemy, member of a French expedition, in a monastery in Egypt and is now carefully preserved in Constantinople. Several photographs of the letter have since been published. The first one was published in the well-known Egyptian newspaper Al-Hilal in November 1904" Muhammad Zafrulla Khan, Muhammad: Seal of the Prophets, Routledge & Kegan Paul, London, 1980 (chapter 12). The drawing of the letter published in Al-Hilal was reproduced in David Samuel Margoliouth, Mohammed and the Rise of Islam, London (1905), p. 365, which is the source of this image.

15. Kisra, M. Morony, The Encyclopaedia of Islam, Vol. V, ed. C.E. Bosworth, E. van Donzel, B. Lewis and C. Pellat, (E.J.Brill, 1980), 185.[1]
18. Coquin, René-Georges (1975). Livre de la consecration du sanctuaire de Benjamin (in French). Paris: Institut Francais D - Archeologie Orientale. pp. 110–112.
21. Reda, Mohammed (1 January 2013). MOHAMMED (S) THE MESSENGER OF ALLAH: محمد رسول الله (ص) [إنكليزي]. Beirut, Lebanon: Dar Al Kotob Al Ilmiyah دار الكتب العلمية. ISBN 978-2-7451-8113-8. Retrieved 14 August 2021.
22. al-Hạlabī, ʻAlī ibn Ibrāhīm Nūr al-Dīn (1964). Insān al-ʻuyūn: fī sīrat al-Amīn al-Maʼmūn (Vol.3) (in Arabic). Musṭạfā al-Bābī al-Hạlabī. pp. 300–306.

25. Ministry of Cultural Affairs of Sultanate of Oman - Advisor to HM the Sultan for Cultural Affairs The Letter of the Prophet Mohammad to the People of Oman - Advisor to HM the Sultan for Cultural Affairs

9. "Sahih al-Bukhari 2940, 2941 - Fighting for the Cause of Allah (Jihaad) - كتاب الجهاد والسير". sunnah.com. Sunnah.com - Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم). Retrieved 18 August 2021.
10. "Mishkat al-Masabih 3926 - Jihad - كتاب الجهاد". sunnah.com. Sunnah.com - Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم). Retrieved 19 August 2021.
13. "Sahih al-Bukhari 7 - Revelation - كتاب بدء الوحى". sunnah.com. Sunnah.com - Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم). Retrieved 19 August 2021.

11. "The Events of the Seventh Year of Migration - The Message". www.al-islam.org. Al-Islam.org. Archived from the original on 5 August 2012. Retrieved 25 August 2013.