1. R. Ahlswede and D.E. Daykin (1978) An inequality for the weights of two families, their unions and intersections, Z, Wahrscheinlichkeitstheorie verw. Gebeite 43, 183–185.
2. A.V. Aho, J.E. Hopcroft and J.D. Ullman (1974)The Design and Analysis of Algorithms, Addison Wesley, Reading, Mass.
3. M. Aigner (1979) Combinatorial Theory, Springer-Verlag.
4. M. Aigner (1981) Producing posets, Disc. Math. 35, 1–15.
5. V.B. Alekseev (1976) O rassifrovke nekotorych Klassov monotonnych mnogoznacnych Funkcij, Z.Vycisl. Mat. i. Mat. Flz 16, 189–198.