“…Nowadays, it is believed that this method is especially suited for dealing with optimal control problems with multiple inequality constraints, whereas it is exactly one of the difficulties in optimal control theory. Many other optimal control approaches share this weakness in this regard (see, e.g., Chan and Guo, 1989; Dmitruk and Osmolovskii, 2014; Girsanov, 1972; Isac and Khan, 2008; Osmolovskii, 2018; Pedregal, 2017; Sun, 2010). Even for optimal control problems with time delay, there are also many successful examples that utilize the Dubovitskii–Milyutin method, such as that presented by Kotarski (1997).…”