Ockendon, D. J., Alston, R. E., Naifeh, K. 1966. The Flavonoids of Psoralea (Leguminosae). Phytochemistry, 5: 601-608.
*Unless otherwise noted all references are to Duke, James A. 1992. Handbook of phytochemical constituents of GRAS herbs and other economic plants. Boca Raton, FL. CRC Press.