VisualDx

VisualDx has this to say about citing one of their images:

How do I cite a VisualDx topic?
Cite the VisualDx topic as a chapter in an electronic book titled VisualDx with editor Lowell A. Goldsmith. There are no page numbers and publication year should be the current year.

EXAMPLE:

Papier A, Craft N, Tharp MD, Shear N. Cocaine Levamisole Toxicity. In: Goldsmith LA, ed. VisualDx. Rochester, NY: VisualDx; 2016. URL: https://www.visualdx.com/visualdx/diagnosis/cocaine+levamisole+toxicity?moduleId=101&diagnosisId=54687. Accessed January 1, 2016.

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