https://123deta.com/document/yr34drxj-thedistributionofthedifferencebetweentwoindependentpoissonrandomvariableswasderivedbyirwin-thedistributionofthedifferencebetweentwocorrelatedpoissonrandomvariableswasrecentlyintroducedbykarlisandntzoufras-whoprovedthatitreducestotheskellamdistribution-poiss.html