Helpman, E. (1997). R%D and productivity: The international connection. National Bureau of Economic Research.
Style de citation Chicago (17e éd.)Helpman, Elhanan. R%D and Productivity: The International Connection. Cambridge: National Bureau of Economic Research, 1997.
Style de citation MLA (9e éd.)Helpman, Elhanan. R%D and Productivity: The International Connection. National Bureau of Economic Research, 1997.
Attention : ces citations peuvent ne pas être correctes à 100%.