“…For application purposes, to avoid anomalous mimimal points, one of the possible approaches is to consider bilevel models, i.e., to find Pareto minima under constraints which are in turn solution sets of other optimization-related problems, see, e.g., [6]. Another more direct way is, besides the Pareto minimum, using other stronger notions of minimality such as proper minima (for various kinds of properness see, e.g., [11,18,22]), strict (or firm) minima (see, e.g., recent papers [10,13]), strong (or ideal) minima (e.g., [8,12]), etc.x ∈ A ⊆ X is called a strong minimum of A if (A − x) ⊆ C. But, usually for a convex cone C and a set A, there hardly is a strong minimum. Fortunately, if C is the lexicographic cone C lex (defined in Sect.…”