Macdougall, J. D. (2008). Nature's clocks: How scientists measure the age of almost everything. University of California Press.
Chicago-čujuhus (17. p.)Macdougall, J. D. Nature's Clocks: How Scientists Measure the Age of Almost Everything. Berkeley: University of California Press, 2008.
MLA-čujuhus (9. p.)Macdougall, J. D. Nature's Clocks: How Scientists Measure the Age of Almost Everything. University of California Press, 2008.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.