It`s based on a study called "Immigration, Offshoring and American Jobs,"? by Giovanni Peri [Email him]of the University of California, Davis, and two others, one of whom is a Professore at an Italian University, which means that, in effect, this offshoring study was partly offshored.
I am prepared to admit that immigrants do create jobs for a number of people:
And in terms of the free market, immigrant entrepreneurs frequently create jobs for other immigrants, usually their wives` relatives, in motels and convenience stores. What they do not do is create more jobs than they take, or provide a net benefit to the American nation.