Holstius, D. M., Pillarisetti, A., Smith, K. R., and Seto, E. Field calibrations of a low-cost aerosol sensor at a regulatory monitoring site in California, Atmos. Meas. Tech., 7, 1121-1131, doi:10.5194/amt-7-1121-2014, 2014.
You don't get what you expect, you get what you inspect.
