Tinea pedis (fungal foot infection). Authoritative facts about the skin from DermNet New Zealand.
Athlete's Foot Treatment - Tinea Pedis - Colorado Springs & Monument, CO
Athlete's Foot/Tinea Pedis – Alexander Foot Care
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Tinea Pedis (Athlete's Foot) - Dermatologic Disorders - MSD Manual Professional Edition
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Athlete's foot - Wikipedia
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Tinea Pedis: The Annoying Fungus on your Feet
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