Preface to 'Special Section: The NASA Stratosphere-Troposphere Exchange Project (STEP) Mid-Latitude Field Experiment.'

Pfister, L., P.B. Russell, E.F. Danielsen, and R.T. Watson (1991), Preface to 'Special Section: The NASA Stratosphere-Troposphere Exchange Project (STEP) Mid-Latitude Field Experiment.', J. Geophys. Res., 96, 17,400.