TY - JOUR AU - R. Lang AU - Peter Bender BT - The Astrophysical Journal DA - Jan-02-1973 DO - 10.1086/151994 PY - 1973 EP - 647 T2 - The Astrophysical Journal TI - Analytic Approximation for the Saturation Behavior of OH Emission Regions UR - http://articles.adsabs.harvard.edu/full/1973ApJ...180..647L VL - 180 SN - 0004-637X ER -