Christou, Jason A2018-06-292018-06-291999b2035825http://hdl.handle.net/1885/144630x, 150 p.enQC446.2.C57 1999Nonlinear opticsGeometrical opticsLaser beamsOptical vortices in beam propagation dynamics199910.25911/5d67b71e28c082018-06-27