 Schrieffer-Wolff transformation for quantum many-body systems by Sergey Bravyi and others

Annals of Physics 326, 2793–2826. By Sergey Bravyi, David P. DiVincenzo and Daniel Loss.

Verified section 3.2, equations (3.6)–(3.15): diagonal/off-diagonal decomposition and second-order projected Hamiltonian. Section 1.1 records the Anderson-to-Kondo application. The wiki two-level example is derived independently.