wichita.edu
…J.W. Petrich, 1997. "Excited-state photophysics of hypericin and its hexamethoxy analog: Intramolecular proton transfer as a nonradiative process in hypericin." Journal of the American Chemical Society, 119(13): p. 2980-2986. 5. English, D.S., K. Das, J.M. Zenner, W. Zhang, G.A. Kraus, R.C. Larock, and J.W. Petrich, 1997. "Hypericin, hypocrellin, and…
https://www.wichita.edu/academics/fairmount_las/chemistry/_faculty/English2.php