Factorization of the transfer matrices for the quantum sl(2) spin chains   and Baxter equation
  It is shown that the transfer matrices of homogeneous sl(2) invariant spin chains with generic spin, both closed and open, are factorized into the product of two operators. The latter satisfy the Baxter equation that follows from the structure of the reducible representations of the sl(2) algebra. 
S. E. Derkachov, A. N. Manashov