Römer, Wolfgang (2010). «Multiple planation surfaces in basement regions: Implications for the reconstruction of periods of denudation and uplift in southern Zimbabwe». Geomorphology114 (3): 199-212. doi:10.1016/j.geomorph.2009.07.001. Bibcode: 2010Geomo.114..199R.
Römer, Wolfgang (2010). «Multiple planation surfaces in basement regions: Implications for the reconstruction of periods of denudation and uplift in southern Zimbabwe». Geomorphology114 (3): 199-212. doi:10.1016/j.geomorph.2009.07.001. Bibcode: 2010Geomo.114..199R.