Birth of discrete Lorenz attractors at the bifurcations of 3D maps with   homoclinic tangencies to saddle points
  It was established in 2006 that bifurcations of three-dimensional diffeomorphisms with a homoclinic tangency to a saddle-focus fixed point with the Jacobian equal to 1 can lead to Lorenz-like strange attractors. In the present paper we prove an analogous result for three-dimensional diffeomorphisms with a homoclinic tangency to a saddle fixed point with the Jacobian equal to 1, provided the quadratic homoclinic tangency under consideration is non-simple. 
S.V.Gonchenko, I.I.Ovsyannikov, J.C.Tatjer
math.DS