REFERENCES
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- Massy , W. S. ( 1991 ). A Basic Course in Algebraic Topology . New York : Springer-Verlag .
- Spiegel , E. ( 2001 ). On the automorphisms of incidence algebras . J. Algebra 239 : 615 – 623 .
- Spiegel , E. and O'Donnell , C. J. ( 1997 ). Incidence Algebras . New York : Marcel Dekker, Inc.
- Communicated by D. Happel.