“…In [12] we considered the following non-linear partial differential equation, describing the price evolution u(x,t), of a mortgage backed security and derived in [13,14,21]: ∂u ∂t = 1 2 ∆u + µ(x,t)∇u − ρ |σ T (x,t))∇u| 2 u + h(x,t) + ξ(t) − (r(t) − τ )h(t) − r(t)u, (x,t) ∈ R N × (0,T ),…”