An amendment providing that Sec. 4 of the bill ceases to be effective if (1) an internationally supervised referendum has been conducted which demonstrates that a majority of non-white South Africans oppose the ban on new investment, and (2) the Secretary certifies that the referdum was conducted in a fair manner and the results are believed to be definitive. Section 4 of the bill provides for restrictions on new investments, including bank loans in South Africa by American concerns or individuals.