PT Journal AU Kim, M Scharf, T Da Costa Assafrao, A Rockstuhl, C Pereira, SF Paul Urbach, H Herzig, HP TI Phase anomalies in Bessel-Gauss beams SO Optics Express PY 2012 BP 28929 EP 28940 VL 20 IS 27 DI 10.1364/OE.20.028929 LA english ER