Littell, M. (1994). Gateways to mathematical investigations (Teacher's ed.). McDougal,Littell & Co..
Chicago-čujuhus (17. p.)Littell, McDougal. Gateways to Mathematical Investigations. Teacher's ed. Dallas: McDougal,Littell & Co., 1994.
MLA-čujuhus (9. p.)Littell, McDougal. Gateways to Mathematical Investigations. Teacher's ed. McDougal,Littell & Co., 1994.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.