  We perform the integration of all iterated singly-unresolved subtraction
terms, as defined in ref. [1], over the two-particle factorized phase space. We
also sum over the unresolved parton flavours. The final result can be written
as a convolution (in colour space) of the Born cross section and an insertion
operator. We spell out the insertion operator in terms of 24 basic integrals
that are defined explicitly. We compute the coefficients of the
Laurent-expansion of these integrals in two different ways, with the method of
Mellin-Barnes representations and sector decomposition. Finally, we present the
Laurent-expansion of the full insertion operator for the specific examples of
electron-positron annihilation into two and three jets.
