Dirisu, J.I., Iyiola, O. and Ibidunni, O.S. 2013. PRODUCT DIFFERENTIATION: A TOOL OF COMPETITIVE ADVANTAGE AND OPTIMAL ORGANIZATIONAL PERFORMANCE (A STUDY OF UNILEVER NIGERIA PLC). European Scientific Journal, ESJ. 9, 34 (Dec. 2013). DOI:https://doi.org/10.19044/esj.2013.v9n34p%p.