In this note all vectors and ε-vectors of a system of m ≤ n linearly independent contravariant vectors in the n-dimensional pseudo-Euclidean geometry of index one are determined. The problem is resolved by finding the general solution of the functional equation F(Au 1 , Au 2 , . . . , Au m ) = (det A) λ · A · F(u 1 , u 2 , . . . , u m ) with λ = 0 and λ = 1, for an arbitrary pseudo-orthogonal matrix A of index one and given vectors u 1 , u 2 , . . . , u m .