Greene, Pamela L. Hall, Dennis G. Media 2: Focal shift in vector beams Originally published in Optics Express on 10 May 1999 (oe-4-10-411) 10 May 1999;media;oe;Optics Express;shift;vector beams;Focal 1999-05-10
    https://opticapublishing.figshare.com/articles/media/Media_2_Focal_shift_in_vector_beams/4952075
10.1364/OE.4.000411.m002