Walker Sally M. Early Bird Earth Science Glaciers. Lerner.
Chicago-čujuhus (17. p.)Walker Sally M. Early Bird Earth Science Glaciers. 2010 2010: Lerner.
MLA-čujuhus (9. p.)Walker Sally M. Early Bird Earth Science Glaciers. Lerner.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.