Parametrices of semi-linear boundary value problems

An earlier work on parametrices and regularity results for semi-linear elliptic boundary value problems has been extended. A construction of parametrices has been made under minimal assumptions, and using paramultiplication non-linear terms of product type are shown to be encompassed by this. Through an investigation of the exotic pseudo-differential operators of type 1,1, the parametrix formula is shown to imply a broad range of local regularity improvements, when the data allow this. A proceedings contribution has appeared and a full manuscript has been submitted.