To cite data from the PBO H₂O data portal, please reference the URL <http://xenon.colorado.edu/portal> and include the following publications within the reference list:

Soil Moisture:
Larson, K.M., E.E. Small, E. Gutmann, A. Bilich, J. Braun, V. Zavorotny, Use of GPS receivers as a soil moisture network for water cycle studies, Geophys. Res. Lett., 35, L24405, doi:10.1029/2008GL036013, 2008.

Snow Depth:
Larson, K.M., E. Gutmann, V. Zavorotny, J. Braun, M. Williams, and F. Nievinski, Can We Measure Snow Depth with GPS Receivers?,Geophys. Res. Lett., 36, L17502, doi:10.1029/2009GL039430, 2009.

Vegetation:
Small, E.E., K.M. Larson, and J. J. Braun, Sensing Vegetation Growth Using Reflected GPS Signals, Geophys. Res. Lett. 37, L12401, doi:10.1029/2010GL042951, 2010.

The creation of these data products was explicitly supported by EAR1144221 and NASA NNX11AL50H. UNAVCO requests that all users of EarthScope PBO data acknowledge EAR-0350028 and EAR-0732947.

Acknowledgements: Our water cycle research has been funded by NSF and NASA: AGS 0740515, EAR 0948957, AGS 0935725, EAR1144221, NNH09ZDA001N, NNX11AL50H, NNH10ZDA001N, NNX10AU84G, NNX13AF43G, and NNX11AR72G.