The concept of lattice implication homomorphism image, which is proved to be a lattice implication algebra, is introduced.
提出了格蕴涵同态像的概念，证明了格蕴涵同态像是格蕴涵代数；
2
In this paper we have given the concept of double-congruence, by which the concepts of double-homomorphism and double-isomorphism in a unary algebra are linked together.