TY - JOUR AU - Benjamin Zwickl AU - Dana Anderson BT - Physical Review A DA - Jan-07-1995 DO - 10.1103/PhysRevA.52.878 PY - 1995 SP - 878 EP - 881 T2 - Physical Review A TI - Spatial structure of light and a nonlinear refractive index generated by fanning in photorefractive media VL - 52 SN - 1050-2947 ER -