• Saint Augustine; The Confessions of Saint Augustine (John K. Ryan translator); Image (1960), ISBN 0-385-02955-1.
• Descartes, René; Meditations on First Philosophy; Bobbs-Merril (1960), ISBN 0-672-60191-5.
• Barzilai, Gad; Law and Religion; The International Library of Essays in Law and Society; Ashgate (2007),ISBN 978-0-7546-2494-3
• Durant, Will (& Ariel (uncredited)); Our Oriental Heritage; MJF Books (1997), ISBN 1-56731-012-5.
• Durant, Will (& Ariel (uncredited)); Caesar and Christ; MJF Books (1994), ISBN 1-56731-014-1
• Durant, Will (& Ariel (uncredited)); The Age of Faith; Simon & Schuster (1980), ISBN 0-671-01200-2.
• Marija Gimbutas 1989. The Language of the Goddess. Thames and Hudson New York
• Gonick, Larry; The Cartoon History of the Universe; Doubleday, vol. 1 (1978) ISBN 0-385-26520-4, vol. II (1994) ISBN#0-385-42093-5, W. W. Norton, vol. III (2002) ISBN 0-393-05184-6.
• Haisch, Bernard The God Theory: Universes, Zero-point Fields, and What's Behind It All -- discussion of science vs. religion (Preface Archived 2012-12-04 at Archive.today), Red Wheel/Weiser, 2006, ISBN 1-57863-374-5
• Lao Tzu; Tao Te Ching (Victor H. Mair translator); Bantam (1998).
• Marx, Karl; "Introduction to A Contribution to the Critique of Hegel’s Philosophy of Right", Deutsch-Französische Jahrbücher, (1844).
• Saler, Benson; "Conceptualizing Religion: Immanent Anthropologists, Transcendent Natives, and Unbounded Categories" (1990), ISBN 1-57181-219-9
• The Holy Bible, King James Version; New American Library (1974).
• The Koran; Penguin (2000), ISBN 0-14-044558-7.
• The Origin of Live & Death, African Creation Myths; Heinemann (1966).
• Poems of Heaven and Hell from Ancient Mesopotamia; Penguin (1971).
• The World Almanac (annual), World Almanac Books, ISBN 0-88687-964-7.
• The Serotonin System and Spiritual Experiences - American Journal of Psychiatry 160:1965-1969, November 2003.
• United States Constitution
• Selected Work Marcus Tullius Cicero
• The World Almanac (for numbers of adherents of various religions), 2005
• Religion [First Edition]. Winston King. Encyclopedia of Religion. Ed. Lindsay Jones. Vol. 11. 2nd ed. Detroit: Macmillan Reference USA, 2005. p7692-7701.
• World Religions and Social Evolution of the Old World Oikumene Civilizations: A Cross-cultural Perspective by Andrey Korotayev, Lewiston, NY: Edwin Mellen Press, 2004, ISBN 0-7734-6310-0.
• Brodd, Jefferey (2003). World Religions. প্ৰকাশক Winona, MN: Saint Mary's Press. ISBN 978-0-88489-725-5. 

On religion definition:

• The first major study: Durkheim, Emile (1976) The Elementary Forms of the Religious Life. London: George Allen & Unwin (in French 1912, English translation 1915).
• Wilfred Cantwell Smith The Meaning and End of Religion (1962) notes that the concept of religion as an ideological community and system of doctrines, developed in the 15th and 16th centuries CE.
• A distillation of the Western folk category of religion: Geertz, Clifford. 1993 [1966]. Religion as a cultural system. pp.  87–125 in Clifford Geertz, The Interpretation of Cultures: Selected Essays. London: Fontana Press.
• An operational definition: Wallace, Anthony F. C. 1966. Religion: An Anthropological View. New York: Random House. (p.  62-66)
• A recent overview: A Scientific Definition of Religion. By Ph.D. James W. Dow.
• Origines de l'homme - De la matière à la conscience, Yves Coppens, De Vive Voix, Paris, 2010
• La preistoria dell’uomo, Yves Coppens, Jaka Book, Milano, 2011

Studies of religion in particular geographical areas:

• A. Khanbaghi. The Fire, the Star and the Cross: Minority Religions in Medieval and Early Modern Iran (IB Tauris; 2006) 268 pages. Social, political and cultural history of religious minorities in Iran, c. 226-1722 AD.