Revised Hyssop Monograph: http://www.hc-sc.gc.ca/dhp-mps/prodnatur/applications/licen-prod/monograph/mono_hyssop-eng.php  3.
Monographie modifiée pour l'hysope :http://www.hc-sc.gc.ca/dhp-mps/prodnatur/applications/licen-prod/monograph/mono_hyssop-fra.php 3.