Goldthorp, W. O. (2009). "Medical Classics: An Account of the Foxglove and Some of its Medicinal Uses by William Withering, published 1785". British Medical Journal. 338: b2189. doi:10.1136/bmj.b2189.
Weisse, Allen B. (January 2010). "A Fond Farewell to the Foxglove? The Decline in the Use of Digitalis". Journal of Cardiac Failure. 16 (1): 45-48. doi:10.1016/j.cardfail.2009.08.001. PMID20123317.
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"ITIS". 30 Ekim 2013 tarihinde kaynağından arşivlendi. Erişim tarihi: 5 Temmuz 2022.
Weisse, Allen B. (January 2010). "A Fond Farewell to the Foxglove? The Decline in the Use of Digitalis". Journal of Cardiac Failure. 16 (1): 45-48. doi:10.1016/j.cardfail.2009.08.001. PMID20123317.