Dr. Singh has published two books and more than fifty research papers in reputed journals. His papers have been published in such journals as Transport Policy, International Journal of Transport Economics, International Journal of Society Systems Science, European Journal of Transport and Infrastructure Research, Journal of Public Transportation, European Transport \ Trasporti Europei, Transportation Research Record, Urban Transport Journal, Telecommunications Policy, IEEE Transactions on Power Systems, International Journal of Emerging Electric Power Systems, Electric Power Systems Research, Applied Soft Computing, Economic and Political Weekly, Studies in Business and Economics, and Productivity. His Scholar.Google h-index is 14 and i-20 index is 13. His research interests are in the areas of Transport Economics and Policy, Infrastructure, Industrial Organization, and Regulatory Economics.