Kim, G.-S. . ., G.-I. . Kim, G.-N. Rim, and S.-N. Jang. “Methods for Comprehensive Analysis of the Economic Effectiveness of Business Activities: Special Reference to R & D Expenditure”. Business Perspective Review, vol. 3, no. 1, Jan. 2021, pp. 1-14, doi:10.38157/business-perspective-review.v3i1.224.