SCOTT PEARL. (1999). EXERCISES IN MENTAL ARITHMETIC.
Chicago-čujuhus (17. p.)SCOTT PEARL. EXERCISES IN MENTAL ARITHMETIC. 1999.
MLA-čujuhus (9. p.)SCOTT PEARL. EXERCISES IN MENTAL ARITHMETIC. 1999.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.