D. L. She, M. an Shao, L. C. Timm, and K. Reichardt, “Temporal changes of an alfalfa succession and related soil physical properties on the Loess Plateau, China”, PAB, vol. 44, no. 2, pp. 189–196, Nov. 2010, doi: 10.1590/S1678-3921.pab2009.v44.799.