Integrable generalised spin ladder models
  We present two new integrable spin ladder models which posses three general free parameters besides the rung coupling J. Wang's systems based on the SU(4) and SU(3/1) symmetries can be obtained as special cases. The models are exactly solvable by means of the Bethe ansatz method. 
Angela Foerster, Jon Links and Arlei Prestes Tonel