Nze, O.N., Okeudo, G.N. and Ejem, E.A. 2021. Trend analysis of the productivity of Nigerian seaports. Journal of Sustainable Development of Transport and Logistics. 6, 2 (Nov. 2021), 81–95. DOI:https://doi.org/10.14254/jsdtl.2021.6-2.5.