Botanical.com (article on Levant Wormseed, primary source of santonin)
doi.org
Woodward, R. B.; Brutschy, F. J.; Baer, Harold (1948). "The Structure of Santonic Acid". Journal of the American Chemical Society. 70 (12): 4216–4221. doi:10.1021/ja01192a070. PMID18105974.
Clemo, George Roger; Haworth, Robert Downs (1930). "CCCXL.—The constitution of santonin. Part III. Proof of the positions of the methyl groups". J. Chem. Soc.: 2579–2582. doi:10.1039/JR9300002579.
Clemo, George Roger; Haworth, Robert Downs; Walton, Eric (1929). "CCCX.—The constitution of santonin. Part I. The synthesis of dl-santonous acid". J. Chem. Soc.: 2368–2387. doi:10.1039/JR9290002368.
Natarajan, Arunkumar; Tsai, C. K.; Khan, Saeed I.; McCarren, Patrick; Houk, K. N.; Garcia-Garibay, Miguel A. (2007-08-01). "The Photoarrangement of α-Santonin is a Single-Crystal-to-Single-Crystal Reaction: A Long Kept Secret in Solid-State Organic Chemistry Revealed". Journal of the American Chemical Society. 129 (32): 9846–9847. doi:10.1021/ja073189o. ISSN0002-7863. PMID17645337.
Woodward, R. B.; Brutschy, F. J.; Baer, Harold (1948). "The Structure of Santonic Acid". Journal of the American Chemical Society. 70 (12): 4216–4221. doi:10.1021/ja01192a070. PMID18105974.
Natarajan, Arunkumar; Tsai, C. K.; Khan, Saeed I.; McCarren, Patrick; Houk, K. N.; Garcia-Garibay, Miguel A. (2007-08-01). "The Photoarrangement of α-Santonin is a Single-Crystal-to-Single-Crystal Reaction: A Long Kept Secret in Solid-State Organic Chemistry Revealed". Journal of the American Chemical Society. 129 (32): 9846–9847. doi:10.1021/ja073189o. ISSN0002-7863. PMID17645337.
Natarajan, Arunkumar; Tsai, C. K.; Khan, Saeed I.; McCarren, Patrick; Houk, K. N.; Garcia-Garibay, Miguel A. (2007-08-01). "The Photoarrangement of α-Santonin is a Single-Crystal-to-Single-Crystal Reaction: A Long Kept Secret in Solid-State Organic Chemistry Revealed". Journal of the American Chemical Society. 129 (32): 9846–9847. doi:10.1021/ja073189o. ISSN0002-7863. PMID17645337.