(en) David Gems, «Alexander Shulgin and Ann Shulgin, PIHKAL, A Chemical Love Story. Alexander Shulgin and Ann Shulgin, TIHKAL, The Continuation», Theoretical Medicine and Bioethics, vol.20, no5, , p.477–479 (ISSN1573-1200, DOI10.1023/A:1009922516904, lire en ligne, consulté le )
(en) David Gems, «Alexander Shulgin and Ann Shulgin, PIHKAL, A Chemical Love Story. Alexander Shulgin and Ann Shulgin, TIHKAL, The Continuation», Theoretical Medicine and Bioethics, vol.20, no5, , p.477–479 (ISSN1573-1200, DOI10.1023/A:1009922516904, lire en ligne, consulté le )
(en) David Gems, «Alexander Shulgin and Ann Shulgin, PIHKAL, A Chemical Love Story. Alexander Shulgin and Ann Shulgin, TIHKAL, The Continuation», Theoretical Medicine and Bioethics, vol.20, no5, , p.477–479 (ISSN1573-1200, DOI10.1023/A:1009922516904, lire en ligne, consulté le )
(en) Alexander Shulgin et Ann Shulgin, Pihkal: a chemical love story, Berkeley, CA, Transform Press, (réimpr.2011), 978p. (ISBN978-0-963-00960-9, OCLC25627628)