Adamski , Wojciech, Anna Chomicka, Agata Stodolska-Nowak, Anna Rzeszotarska, and Andrzej Dmitriew. “Effectiveness of Astigmatism Correction and Spherical Power Calculation Using the Barrett Formula and Alcon® Verion™ Vision Planner 3.1”. OphthaTherapy. Therapies in Ophthalmology 5, no. supl. 3 (November 30, 2018): 10-15. Accessed May 18, 2024. https://www.journalsmededu.pl/index.php/ophthatherapy/article/view/717.