Abelian Sandpile Model on the Husimi Lattice of Square Plaquettes
  An Abelian sandpile model is considered on the Husimi lattice of square plaquettes. Exact expressions for the distribution of height probabilities in the Self-Organized Critical state are derived. The two-point correlation function for the sites deep inside the Husimi lattice is calculated exactly. 
Vl.V.Papoyan and R.R.Shcherbakov