:: deftheorem Def6 defines nat_hom ALGSTR_4:def 6 :
for M being non empty multMagma
for R being compatible Equivalence_Relation of M
for b₃ being Function of M,(M ./. R) holds
( b₃ = nat_hom R iff for v being Element of M holds b₃ . v = Class (R,v) );