Spaces with contravariant and covariant affine connections and metrics
  The theory of spaces with different (not only by sign) contravariant and covariant affine connections and metrics [}$(\bar{L}_n,g)$\QTR{it}{-spaces] is worked out within the framework of the tensor analysis over differentiable manifolds and in a volume necessary for the further considerations of the kinematics of vector fields and the Lagrangian theory of tensor fields over}$(\bar{L}_n,g)$\QTR{it}{-spaces. The possibility of introducing affine connections (whose components differ not only by sign) for contravariant and covariant tensor fields over differentiable manifolds with finite dimensions is discussed. The action of the deviation operator, having an important role for deviation equations in gravitational physics, is considered for the case of contravariant and covariant vector fields over differentiable manifolds with different affine connections A deviation identity for contravariant vector fields is obtained. The notions covariant, contravariant, covariant projective, and contravariant projective metrics are introduced in (}$\bar{L}_n,g$\{)-spaces. The action of the covariant and the Lie differential operators on the different type of metrics is found. The notions of symmetric covariant and contravariant (Riemannian) connections are determined and presented by means of the covariant and contravariant metrics and the corresponding torsion tensors. The different types of relative tensor fields (tensor densities) as well as the invariant differential operators acting on them are considered. The invariant volume element and its properties under the action of different differential operators are investigated. 
S. Manoff