Helpman, E. (1998). General purpose technologies and economic growth. MIT Press.
芝加哥风格引文Helpman, Elhanan. General Purpose Technologies and Economic Growth. Cambridge, Mass.: MIT Press, 1998.
MLA引文Helpman, Elhanan. General Purpose Technologies and Economic Growth. MIT Press, 1998.
警告：这些引文格式不一定是100％准确.