@incollection{Varssano12,
author = {David Varssano},
title = {Etiology and Clinical Presentation of Astigmatism},
booktitle = {Astigmatism},
publisher = {IntechOpen},
address = {Rijeka},
year = {2012},
editor = {Michael Goggin},
chapter = {2},
doi = {10.5772/18338},
url = {https://doi.org/10.5772/18338}
}