APA-čujuhus (7. p.)
(1994). Project learning tree: Environmental education activity guide (2nd.). Project Learning Tree.
Chicago-čujuhus (17. p.)
Project Learning Tree: Environmental Education Activity Guide. 2nd. Washington: Project Learning Tree, 1994.
MLA-čujuhus (9. p.)
Project Learning Tree: Environmental Education Activity Guide. 2nd. Project Learning Tree, 1994.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.