APA
Bound J., Solon G., . (1998). Double trouble : on the value of twins-based estimation of the return to schooling. Cambridge, Mass: National Bureau of Economic Research.
Chicago
Bound John, Solon Gary, . 1998. Double trouble : on the value of twins-based estimation of the return to schooling. Cambridge, Mass: National Bureau of Economic Research.
Harvard
Bound J., Solon G., . (1998). Double trouble : on the value of twins-based estimation of the return to schooling. Cambridge, Mass: National Bureau of Economic Research.
MLA
Bound John, Solon Gary, . Double trouble : on the value of twins-based estimation of the return to schooling. Cambridge, Mass: National Bureau of Economic Research. 1998.