:: deftheorem Def9 defines DualHomomorphism CONLAT_2:def 9 :
for C being FormalContext
for b2 being Homomorphism of ((ConceptLattice C) .:),(ConceptLattice (C .:)) holds
( b2 = DualHomomorphism C iff for CP being strict FormalConcept of C holds b2 . CP = CP .: );