On the existence of efficient points in locally convex spaces. - Truong Xuan Duc Ha (J. Glob. Optim., 1994)

New Order Relations in Set Optimization. - Johannes Jahn; Truong Xuan Duc Ha (J. Optim. Theory Appl., 2011)

Slopes, Error Bounds and Weak Sharp Pareto Minima of a Vector-Valued Map. - Truong Xuan Duc Ha (J. Optim. Theory Appl., 2018)

A new concept of slope for set-valued maps and applications in set optimization studied with Kuroiwa's set approach. - Truong Xuan Duc Ha (Math. Methods Oper. Res., 2020)

Strict Efficiency in Set Optimization Studied with the Set Approach. - Truong Xuan Duc Ha (J. Optim. Theory Appl., 2025)