Roger Coote. Knowledge Masters: The Earth. Young Learner Publications.
Chicago-čujuhus (17. p.)Roger Coote. Knowledge Masters: The Earth. Young Learner Publications.
MLA-čujuhus (9. p.)Roger Coote. Knowledge Masters: The Earth. Young Learner Publications.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.