:: deftheorem defines is_epimorphism MSUALG_3:def 8 :
for S being non empty non void ManySortedSign
for U1, U2 being MSAlgebra over S
for F being ManySortedFunction of U1,U2 holds
( F is_epimorphism U1,U2 iff ( F is_homomorphism U1,U2 & F is "onto" ) );