(2004). The World of Learning (55th ed.). Europa.
Chicago-čujuhus (17. p.)The World of Learning. 55th ed. London: Europa, 2004.
MLA-čujuhus (9. p.)The World of Learning. 55th ed. Europa, 2004.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.