Consider two topological spaces
X and Y , two maps f,g : X → Y , and a relation R on Y , R ⊂ Y × Y . A
Lefschetz-type theorem is established with regard to the existence of an x ∈ X such
that g(x)Rf(x). Several ideas related to the Lefschetz Fixed Point Theorem,
such as periodic point theorems, local fixed point index, asymptotic fixed
point and periodic point theorems, are carried over to this more general
situation.