“…In addition to the application to the non-vanishing of Yoshida lifts, our main motivation for the explicit Petersson norm formula for Yoshida lifts of type (I) originates from the study on the congruences between Hecke eigen-systems of Yoshida lifts and stable forms on GSp(4), the so-called Yoshida congruence as well as its application to the Bloch-Kato conjecture for special values of Asai L-functions. The Yoshida congruence was first investigated by the independent works [BDSP12] and [AK13], where the Petersson norm formula was used to relate the congruence primes of Yoshida lifts of type (I) to special values of the Rankin-Selberg L-functions. More precisely, in [BDSP12, Corollary 9.2] and [AK13, Theorem 6.6], the authors proved that if a prime p divides the algebraic part of the L-values L(f 1 ⊗ f 2 , k 1 + k 2 + 2), then p is a congruence prime for Yoshida lifts attached to a pair of elliptic newforms (f 1 , f 2 ) of weight (2k 1 + 2, 2k 2 + 2) under some restricted hypotheses.…”