TY  - RPRT
TI  - Diffraction-free beams remain diffraction free under all paraxial optical transformations.
AU  - KB Wolf
PY  - 1988
DO  - 10.1103/physrevlett.60.757
UR  - https://pubmed.ncbi.nlm.nih.gov/10038644/
ID  - 10038644
ER  -