For a detailed description of the methodology behind the quality flags we refer to:

Dorigo, W.A. , Xaver, A. Vreugdenhil, M. Gruber, A., Hegyiová, A. Sanchis-Dufau, A.D., Zamojski, D. , Cordes, C., Wagner, W., and Drusch, M. (2013). Global Automated Quality Control of In Situ Soil Moisture data from the International Soil Moisture Network. Vadose Zone Journal, 12, 3, doi:10.2136/vzj2012.0097

Dorigo, W., I. Himmelbauer, D. Aberer, L. Schremmer, I. Petrakovic, L. Zappa, W. Preimesberger, A. Xaver, and 54 Co-Authors (2021). The International Soil Moisture Network: serving Earth system science for over a decade Hydrol. Earth Syst. Sci. Discuss., preprint/in review, 2021, doi:10.5194/hess-2021-2

!! These papers shall be cited when you use the quality flags for your research !!