∀ {α : Type u_1} {β : Type u_2} {γ : Type u_3} {mα : MeasurableSpace α} {mβ : MeasurableSpace β}
  {mγ : MeasurableSpace γ} {a : α} {E : Type u_4} [inst : NormedAddCommGroup E] {η : ProbabilityTheory.Kernel (α × β) γ}
  [ProbabilityTheory.IsSFiniteKernel η] [inst_2 : NormedSpace ℝ E] {f : β × γ → E},
  MeasureTheory.StronglyMeasurable f → MeasureTheory.StronglyMeasurable fun x => ∫ (y : γ), f (x, y) ∂η (a, x)