Horowitz, B. The Hard Thing About Hard Things. Harper Business.
Chicago-čujuhus (17. p.)Horowitz, Ben. The Hard Thing About Hard Things. Harper Business.
MLA-čujuhus (9. p.)Horowitz, Ben. The Hard Thing About Hard Things. Harper Business.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.