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10, 18–20 (1971). See also Crawley-Dilworth, Hall-Dilworth.: Dinolt, G. W. See Brualdi-Dinolt.
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4. Dilworth, R. P.:The arithmetical theory of Birkhoff lattices. Duke Math. J. 8, 286–299 (1941).
5. Dilworth, R. P.:Dependence relations in a semimodular lattice. Duke Math. J. 11, 575–587 (1944).