Gaya APA

AKPAN, U, F. (2011). Cointegration, Causality and Wagner's Hypothesis: Time Series Evidence for Nigeria, 1970-2008 . Korea: Hanyang Economic Research Institute.

Gaya MLA

AKPAN, Usenobong, F. "Cointegration, Causality and Wagner's Hypothesis: Time Series Evidence for Nigeria, 1970-2008". Korea: Hanyang Economic Research Institute, 2011. Artikel.