Ford KA, Ebisuzaki Y, Boyle PD (1998). Methylxanthines. II. Anhydrous Theobromine. Acta Crystallographica Section C Crystal Structure Communications. 54 (12): 1980—1983. Bibcode:1998AcCrC..54.1980F. doi:10.1107/S0108270198009469.
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Ford KA, Ebisuzaki Y, Boyle PD (1998). Methylxanthines. II. Anhydrous Theobromine. Acta Crystallographica Section C Crystal Structure Communications. 54 (12): 1980—1983. Bibcode:1998AcCrC..54.1980F. doi:10.1107/S0108270198009469.