Separable expansions of thet-matrix

A recent result of Osborn on the non-convergence of separable expansions of the t-matrix $\text{(}\text{p}\text{,}\text{p}\text{′;z)}$ is discussed. It is shown that the theoretical difficulties arise from large values of $\text{p}$ and $\text{p}\text{′}$, and cause no difficulties in practical situations.