Swanson, Susan K.; Bahr, Jean M.; Bradbury, Kenneth R.; Anderson, Kristin M. (Februar 2006): «Evidence for preferential flow through sandstone aquifers in Southern Wisconsin», Sedimentary Geology. 184 (3–4): 331–342. Bibcode:2006SedG..184..331S. doi:10.1016/j.sedgeo.2005.11.008.
Swanson, Susan K.; Bahr, Jean M.; Bradbury, Kenneth R.; Anderson, Kristin M. (Februar 2006): «Evidence for preferential flow through sandstone aquifers in Southern Wisconsin», Sedimentary Geology. 184 (3–4): 331–342. Bibcode:2006SedG..184..331S. doi:10.1016/j.sedgeo.2005.11.008.
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Powell, Darryl: «Quartzite», Mineral Information Institute. Arkivert fra originalen den 2. mars 2009
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Powell, Darryl: «Quartzite», Mineral Information Institute. Arkivert fra originalen den 2. mars 2009