Primary Source #191:

Prathap P, Asokan N. Familial koilonychia. Indian J Dermatol. 2010;55(4):406-407. doi:10.4103/0019-5154.74575

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Feel free to use any of the images showcased on this website. Please cite both this website (UNC School of Medicine Dermatology Image Library - http://med.unc.edu/dil) and the primary source of the image as references.
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