""Contents""; ""Â0. Synopsis""; ""Â1. The manifolds M[sub(n)](k,1)""; ""Â2. The foldings C(k,1)""; ""Â3. The lens spaces as branched double coverings""; ""Â4. C(k,h) = S[sup(3)]""; ""Â5. The manifolds M[sub(n)](k,h)""; ""Â6. The fundamental group of M[sub(n)](k,h)""; ""References""