Derric, Michele R., Dusan Stulik, and James M. Landry, eds. "Gum Tragacanth (Astragalus gummifer)." in Infrared Spectroscopy in Conservation Science: Scientific Tools for Conservation. Los Angeles: Getty Conservation Institute, 1999.

Derric, Michele R., Dusan Stulik, and James M. Landry, eds. "Gum Tragacanth (Astragalus gummifer)." in Infrared Spectroscopy in Conservation Science: Scientific Tools for Conservation. Los Angeles: Getty Conservation Institute, 1999.