Non-Negative Definite Solutions of Certain Differential and Functional Equations Reports of Meetings E. LUKÁCS — 1969 Aequationes mathematicae
Non Negative Definite Solutions of Certain Differential and Functional Equations (Short Communication) E. LUKACS — 1969 Aequationes mathematicae
On a functional equation which occurs in a characterization problem. R.G. Laha; E. Lukacs — 1977 Aequationes mathematicae
On a functional equation which occurs in a characterization problem. (Short Communication). R.G. Laha; E. Lukacs — 1977 Aequationes mathematicae
Homological Characterization of Lean Algebras. V. Dlab; I. Ágoston; E. Lukács — 1993 Manuscripta mathematica