The referenced paper [Appl. Opt. 58, 3767 (2019) [CrossRef] ] has been retracted.
© 2019 Optical Society of America
The paper  has been retracted at the request of the author because Mr. Verma was not authorized to submit the work for publication and the appropriate contributors are neither acknowledged nor listed as co-authors.
The original article was published 6 May 2019, and was retracted on 17 June 2019.
1. S. Verma, “All-circular hole microstructured fiber with high birefringence and low confinement loss,” Appl. Opt. 58, 3767–3774 (2019). [CrossRef]