A lattice theoretic view of K-density.

César Fernández P. S. Thiagarajan A lattice theoretic view of K-density. 139-153 1984 conf/apn/1984 European Workshop on Applications and Theory in Petri Nets db/conf/apn/apn1984.html#FernandezT84 http://dx.doi.org/10.1007/3-540-15204-0_9