Shin, Y. H., J. L. Koo, and K. H. Roh. “An Optimal Consumption and Investment Problem With Quadratic Utility and Subsistence Consumption Constraints: A Dynamic Programming Approach”. *Mathematical Modelling and Analysis*, Vol. 23, no. 4, Oct. 2018, pp. 627-38, doi:10.3846/mma.2018.038.