could you please add a reference for the notions you used here (and also in other places) ?

[algorithmx]

could you please make this piece of code self-contained, by providing a reference with complete definitions of all concepts used here? https://github.com/yuehhua/GeometricFlux.jl/blob/5765e503dd45b2a87d300d9b3229e3f4d0b54f38/src/layers/msgpass.jl#L4

(sorry it wasn't a typo ...)