Charles S. Cockell; M. Dale Stokes (August 2006). "Hypolithic Colonization of Opaque Rocks in the Arctic and Antarctic Polar Desert". Arctic, Antarctic, and Alpine Research. 38 (3): 335–342. doi:10.1657/1523-0430(2006)38[335:HCOORI]2.0.CO;2. S2CID140167789.
Charles S. Cockell; M. Dale Stokes (August 2006). "Hypolithic Colonization of Opaque Rocks in the Arctic and Antarctic Polar Desert". Arctic, Antarctic, and Alpine Research. 38 (3): 335–342. doi:10.1657/1523-0430(2006)38[335:HCOORI]2.0.CO;2. S2CID140167789.