Calculation of the Observationally Small Cosmological Constant in the   Model of Six-Dimensional Warped Brane-Bolt World
  In the 6-dimensional model of warped compactification based on the euclidean AdS Reissner-Nordstrom metric it is possible to escape artificial 4-brane's stress-energy tensor anistropy necessary for fulfillment of Israel junction conditions by introducing in 3+1 spacetime of the cosmological constant which turns out to be ${}\sim G^2$ ($G$ - Newton's constant) and acquires the value compatible with observations. 
Boris L. Altshuler