What is the formulation used to calculate noises from correlated sources?

[Msmatrixin]

I am clear with the fact that if there are independent noise sources in a circuit then how will we calculate the overall noise of that circuit.
But when it comes to correlated sources(the best way i see is, in a typical analog circuit consisting op-amp and ADC, the output noise of the amplifier is being fed to the next stage /ADC), how do i calculate the overall noise. ?

 

[KlausST]

Hi,

If two noise sources are correlated, then you add them the usual way (without using square and square root).

If two noise sources are independent, then you add them using the square and square root method.

Klaus