http://www.vanderbilt.edu/AnS/Chemistry/Rizzo/chem224/alkaloids.pdf (http://www.vanderbilt.edu/AnS/Chemistry/Rizzo/chem224/alkaloids.pdf)
http://www.wiley-vch.de/books/biotech/pdf/v08a_alk.pdf (http://www.wiley-vch.de/books/biotech/pdf/v08a_alk.pdf)
Post 303419 (missing)
(Natrix: "alkaloids", General Discourse)