<div class="section" id="some-background-references"> <h1>Some background references</h1> <ol class="arabic simple">

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<li>Aigner, M. 1984. Uses of the Diagram Lattice.

Mitteilgn d.Mathem.Sem.Uni.Giessen 103 : 61-77</li>

<li>Annoni, P. 2007. Different ranking methods: potentialities and

pitfalls for the case of European opinion poll. Environ.Ecol.Stat. 14:453-471.</li>

<li>Atkinson, M. D. 1989. The complexity of Orders.

Pages 195-230 in I. Rival, ed. Algorithms and Order NATO ASI series, Series C: Mathematical and Physiscal Sciences, Vol. 255 ISBN 0-7923-0007-6. Kluwer Academic Publishers, Dordrecht.</li>

<li>Babic, D. and N. Trinajstic. 1992. Resonance Energy of Conjugated

Hydrocarbons Derived by Cluster Expansions. Croatica Chemica Acta 65:881-892.</li>

<li>Balaban, A. T. 1976. Chemical Applications of Graph Theory.

Academic Press, London.</li>

<li>Barthelemy, J. P., B. Leclerc, and B. Monjardet. 1986. On the use of

Ordered Sets in Problems of Comparison and Consensus of Classifications. J.of Classif. 3:187-224.</li>

<li>Bonchev, D. and E. Gordeeva. 2000. Hierarchical Partially Ordered

Sets Based on Topological Complexity. Match 42:85-117.</li>

<li>Brightwell, G. R. 1997. Partial Orders. Pages 52-69 in L. C. Barneke,

ed. Graph Connections.</li>

<li>Brightwell, G. R. and D. B. West. 2000. Partially ordered Sets.

Pages 717-752 in K. R. Rosen, ed. Handbook of Discrete and Combinatorial Mathematics. Boca Raton.</li>

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