Byszewski, L. (2004) “Strong maximum principles for implicit parabolic functional-differential problems together with initial inequalities”, Annales Universitatis Paedagogicae Cracoviensis Studia Mathematica, 4, pp. 9–16. Available at: https://studmath.uken.krakow.pl/article/view/13304 (Accessed: 31 October 2026).