GIBSON, J. (1990). SUPERVISORY CHALLENGES. MERRILL PUB. CO.
Chicago-čujuhus (17. p.)GIBSON, J.W. SUPERVISORY CHALLENGES. COLUMBUS: MERRILL PUB. CO, 1990.
MLA-čujuhus (9. p.)GIBSON, J.W. SUPERVISORY CHALLENGES. MERRILL PUB. CO, 1990.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.