Reviva Labs Dual Source Vitamin C Serum, 1 ozReviva Dual Source Vitamin C Serum Aminopropyl Ascorbyl Phosphate + Sodium Ascorbate. Anti Aging Skin Care. Dual Source Vitamin C Serum by Reviva Labs is more than simply a double dose of "C". It is two separate C extracts combined into one potent concentrate. It's also a gentle, effective skin brightener that reduces the appearance of dark age spots. Reviva's dual source Serum also helps promote collagen synthesis and corrects existing environmental