Swan, Trevor W. (1956). "Economic Growth and Capital Accumulation". Economic Record32 (2): 334–361. doi:10.1111/j.1475-4932.
Barelli, Paulo (2003). "Inada conditions imply that production function must be asymptotically Cobb–Douglas". Economics Letters81 (3): 361–363. doi:10.1016/S0165-1765(03)00218-0.