George E. Williams (2000). „Geological constraints on the Precambrian history of Earth's rotation and the Moon's orbit“. Reviews of Geophysics. 38 (1): 37–60. Bibcode:2000RvGeo..38...37W. doi:10.1029/1999RG900016.
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George E. Williams (2000). „Geological constraints on the Precambrian history of Earth's rotation and the Moon's orbit“. Reviews of Geophysics. 38 (1): 37–60. Bibcode:2000RvGeo..38...37W. doi:10.1029/1999RG900016.