“…If d 2 = 0, this is the Cox-Ingersoll-Ross (CIR) process, which is used in finance [15]. The study of Pearson diffusions began with Kolmogorov [20] and Wong [48], see also [1, 2, 17, 22, 23, 45]. Let p 1 ( x, t ; y ) denote the conditional probability density of x = X 1 ( t ) given y = X 1 (0), i.e., the transition density of this time-homogeneous Markov process.…”