Sachs , I. (1964). Planning and Economic Development. PWN.
Chicago-čujuhus (17. p.)Sachs , Ignacy. Planning and Economic Development. Warsaw: PWN, 1964.
MLA-čujuhus (9. p.)Sachs , Ignacy. Planning and Economic Development. PWN, 1964.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.