Hankel operators in the Bergman space and Schatten 𝑝-classes: The case 1<𝑝<2

K. Zhu proved in Amer. J. Math. 113 (1991), 147-167, that, for 2 ≤ p > ∞ 2 p >, the Hankel operators H f H₅ and H f ¯ H ₅ on the Bergman space belong to the Schatten class C p {C}₏ if and only if the mean oscillation MO (f) (z) = | f | 2 ~ (z) − | f ~ (z) | 2 1 / 2 (f) (z) = \ {|f|^{2} (z) - | f (z) |^2\}^1/2 belongs to L p (D, (1 − | z