TY - JOUR AU - A. Streater AU - John Cooper BT - Journal of Quantitative Spectroscopy and Radiative Transfer DA - Jan-01-1988 DO - 10.1016/0022-4073(88)90019-2 PY - 1988 SP - 49 EP - 55 T2 - Journal of Quantitative Spectroscopy and Radiative Transfer TI - Direct probing of the radiation field in optically thick environments VL - 39 SN - 00224073 ER -