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D N Jha, Drink of Immortality: Essays on Distillation and Alcohol Use in Ancient India (2020)
Matthew Clark, The Tawny One and Botanical Ecstasies.
James McHugh, Unholy Brews. Soma in the appendix.
Jan E.M. Houben, Soma Haoma (Electronic Journal of Vedic Studies, Vol. 9, Issue 1, 2003: 1-2.http://dx.doi.org/10.11588/ejvs.2003.1.786)
William Scott Shelley, Soma and the Indo-European Priesthood : Cereal Cultivation and the Origins of Religion