Subjective Refraction Techniques. iDOCS. Ophthalmology Foundation. https://www.ophthalmologyfoundation.org/uploads/2/1/5/1/21511986/subjective_refraction_techniques.pdf. Accessed January 15, 2026.
Reliability of Subjective Refraction: A Systematic Review. Ophthalmic and Physiological Optics. https://onlinelibrary.wiley.com/doi/10.1111/opo.12738. Accessed January 15, 2026.
Refraction. EyeWiki. American Academy of Ophthalmology. https://eyewiki.aao.org/Refraction. Accessed January 15, 2026.
Visual Acuity Measurement. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK563298/. Accessed January 15, 2026.
Asthenopia. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK470405/. Accessed January 15, 2026.
Vision Therapy. American Optometric Association. https://www.aoa.org/healthy-eyes/eye-and-vision-conditions/vision-therapy. Accessed January 15, 2026.